• Journal of Information Technology Applications and Management
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• 제12권4호
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• pp.25-31
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• 2005

We know that the Hurst Exponent (HE) is a real number in [0, 1] which denotes randomness of time series. in this research, we suggest non-linear analysis of human biological signals through HE. The feasibility of human biological signals using inductive incitement provides Some diagnosis for active treatment. In our experiment, we measured the heartbeat through the MCG, 29 healthy and 34 abnormal subjects ostensibly. The raw data of acupuncture incitement are supported by opinions of gross examination and pathological diagnosis. The mean values of HE are 0.345, 0.755 and 0.805 for the periods of before, during and after acupuncture treatment, respectively in case of abnormal subjects. On the other hand, the mean values, 0.808, 0.797 and 0.785 are for normal cases, correspondingly. From this data, we show that HE is very significant in abnormal controls according to an acupuncture incitement, and the incitement effect is evidently extracted in abnormal subjects. But, in normal subjects, the incitement effect is meaningless.

• 전자공학회논문지
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• 제51권9호
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• pp.200-207
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• 2014

부정맥 심전도 신호는 전도장애 및 발생부위에 따라 특정 부위에서 비정상 모양을 띄는 특이심박을 포함하고 있다. 특이심박은 부정맥 등 다양한 질환을 진단 및 분류하는데 있어 유용하기 때문에 부정맥 심전도 신호에서 특이심박의 검출은 매우 중요하다. R-peak점에서의 전위, 첨도 및 R-R 간격은 심전도 신호가 R파에서 가지는 특성이다. 본 논문에서는 이를 바탕으로 특이심박 검출 방법을 제안한다. 제안한 방법은 특이심박이 확실할수록 특성값이 평균에서 크게 벗어난다는 점을 기반으로 평균과 표준편차를 이용하여 순차적으로 특이심박을 검출한다. MIT-BIH 부정맥 데이터베이스 중 R파 왜곡을 가지는 15개의 심전도 신호에 대해 기존의 고정된 문턱값을 사용한 검출 방법과 제안한 방법을 적용하여 특이심박을 검출하여 비교하였다. 실험을 통해 민감도를 약 50~70%에서 제안한 방법을 통해 97%로 크게 상향할 수 있었다.

• 한국통신학회논문지
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• 제40권4호
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• pp.731-739
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• 2015

부정맥 심전도 신호에는 전도장애 및 발생부위에 따라 다양한 비정상 모양을 띄는 특이심박들이 포함되어 있고, 이들 특이심박은 부정맥 등의 심장질환을 진단하는데 있어 매우 중요하다. 본 논문에서는 심실질환에 관련한 PVC 특이심박 검출 알고리즘을 제안한다. PVC 특이심박에서는 심전도 신호의 구성요소 가운데 QRS 군의 왜곡이 발생하는 특징이 있다. 따라서 QRS 군의 왜곡 정도에 따라 PVC 특이심박을 검출할 수 있다. 먼저 R-peak의 전위, 첨도, 주기를 사용하여 QRS 군의 왜곡을 정량화하고, 이들 값들의 평균과 표준편차를 이용하여 정상 심박과의 왜곡의 정도에 따라 PVC 특이심박을 검출한다. 제안한 알고리즘은 MIT-BIH 부정맥 데이터베이스 중 심실질환과 관계되는 AAMI-V class 타입의 특이심박을 평균 98% 이상을 검출할 수 있었다.

• 한국위성정보통신학회논문지
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• 제9권1호
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• pp.85-89
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• 2014

심전도(electrocardiography, ECG)는 심장박동을 할 때, 발생하는 탈분극과 재분극으로 심장의 전위변화를 시간의 흐름에 따라 파형으로 표현한 것이다. 의료기관에서는 심전도신호를 이용하여 환자의 심장질환을 진단한다. 일반적으로 사람의 정상적인 심장박동수는 1분에 60-100회 이다. 만약 정상적인 심장박동 수보다 느리거나 빠르다면 부정맥이라고 한다. 본 논문에서는 심전도신호에서 R-peak를 검출하여, R-R 간격을 구하고 부정맥 중에 서맥(bradycardia)과 빈맥(tachycardia) 구간을 검출하는 알고리즘을 제안하고 모의실험을 하였다.

• 대한의용생체공학회:의공학회지
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• 제29권6호
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• pp.466-476
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• 2008

The more people use ambulatory electrocardiogram(ECG) for arrhythmia detection, the more researchers report the automatic classification algorithms. Most of the previous studies don't consider the un-balanced data distribution. Even in patients, there are much more normal beats than abnormal beats among the data from 24 hours. To solve this problem, the hierarchical classification using 21 features was adopted for arrhythmia abnormal beat detection. The features include R-R intervals and data to describe the morphology of the wave. To validate the algorithm, 44 non-pacemaker recordings from physionet were used. The hierarchical classification model with 2 stages on domain knowledge was constructed. Using our suggested method, we could improve the performance in abnormal beat classification from the conventional multi-class classification method. In conclusion, the domain knowledge based hierarchical classification is useful to the ECG beat classification with unbalanced data distribution.

• 한국임상수의학회지
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• 제14권1호
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• pp.112-117
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• 1997

12-month-old Buldig and 3-year-old German Shepherd, treated with corticosteroids duringthe late pregnancy, were referred to the Veterinary Teaching Hospital, Chonnam National University, with chief complaints of vaginal discharge. Radiographic, ultrasonographic and surgical findings that obtained from each cases were as follows; case I: Radiographic findings were identified 2 fetuses that were normal skeleton, however, fetal viability could not be determined. Ultrasonographic findings were identified absence of fetal heartbeat and fetal movement, abnormal echogenicity of the abdominal visera, and echogenic materials remaining within the fetal fluid. After hysterotomy, macroscopic findings of uterus were liquefied materials remaining within the uterine lumen. Fetuses were excessively autolysis (falling off the hair, depression of the eye, and necrosis of the abdormal visera and skin). case II: Radiographic findings were identified irregular fetal structures and fetal movement, loss of recognizable fetal anatomy, dislocation of fetal veterbrae and echogenic materials remaining within the uterine lumen. After ovariohysterectomy, macroscopic finding of uterus and fetus were thickened uterine wall, yellowish-brown colored administration of corticosteroids during gestation should be contraindicated because fetal death is inducced. Ultrasonography has an advantage over radiography in that it permits evaluation of fetal viability.

• 대한임상독성학회지
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• 제17권2호
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• pp.132-134
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• 2019

Green tobacco sickness is an illness caused by dermal exposure to nicotine. The common symptoms of the disease include dizziness, headache, nausea, vomiting, severe general weakness, fluctuations of blood pressure or heartbeat, abdominal cramping, chills, increased sweating, salivation, and difficulty breathing. A 79-year-old female arrived at the emergency room for an evaluation of sudden onset dizziness. Magnetic resonance imaging and angiography of the brain did not show any relevant abnormal findings. Four days later, with supportive care, she said that she had harvested green tobacco for six hours on the day of admission and the tobacco harvest was the first time in her life. She sweated excessively during the hot and humid weather and the tobacco leaves were wet from rain the night before. The serum cotinine tested at five days of admission was 16ng/ml. She was diagnosed with acute nicotine poisoning by her clinical symptoms and the half-life of cotinine in the blood.

• 대한의생명과학회지
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• 제25권3호
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• pp.237-246
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• 2019

Left ventricular hypertrophy (LVH) refers to the expansion and the enlarged myocardium due to the increased resistance to ejection from the left ventricle to the aorta and/or the periphery, or the long-term burden imposed by the blood increase. Hypertension is a major risk factor that accounts for more than 50% of the causes of cardiovascular disease. If hypertension endure in the long term, the myocardium responds to abnormal heartbeat in the heart. Therefore, the prevalence of left ventricular hypertrophy also increases. As a result of genome-wide association study (GWAS) analysis for European people, PDGFC, MARK3, and BCL2 were related to blood pressures. In this study, the genetic polymorphisms of PDGFC, MARK3, and BCL2 were extracted and selected based on Korean genomic and epidemiologic data, and then logistic regression analysis was performed on LVH. As a result, one SNP (rs9307953) in PDGFC gene, four SNPs (rs6575983, rs17679475, rs2273703 and rs10141388) in MARK3 gene and two SNPs (rs17756073 and rs17070739) in BCL2 gene were statistically significant. The rs6575983 of the MARK3 gene showed the highest significance level ($P=7.2{\times}10^{-3}$) among the SNPs and the relative risk of 1.08 (95% confidence interval: 1.06 to 1.45). These results suggest that the polymorphisms of PDGFC, MARK3, and BCL2 not only affect European blood pressures but also correlate with LVH in Korean. These results suggest that increased understanding of the genetic correlations of the pathogenesis of LVH.

• 한국정보통신학회논문지
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• 제24권1호
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• pp.37-43
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• 2020

최근 심전도 (ECG) 신호를 사용하여 심장병을 진단하는 많은 연구가 이루어지고 있다. 이러한 심전도 신호는 비정상적인 심장 상태를 나타내는 부정맥을 모니터링하고 진단하는 데 유용하게 쓰인다. 본 논문에서는 1차원 합성곱 신경망을 사용하여 ECG 신호에 대하여 부정맥을 분류하는 시스템을 제안한다. 제안하는 신경망 알고리즘은 부정맥 신호의 특징을 세밀하게 추출하도록 4개의 합성곱 계층으로 구성하고 매개변수를 최적화하도록 설계되었다. MIT-BIH 부정맥 데이터베이스에 대해 학습한 신경망은 시뮬레이션을 통해 99% 이상의 정확도의 분류 성능을 가진다는 것을 보여준다. 비교적 합성곱 커널의 개수가 많을수록 ECG 신호의 특성을 더 잘 나타내기 때문에 좋은 성능을 나타내는 것으로 분석되었다. 또한 제안된 신경망을 활용한 실제 시스템을 구현하여 실시간으로 부정맥을 분류하는 결과를 검증하였다.

• 한국수정란이식학회지
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• 제23권1호
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• pp.5-11
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• 2008

Serial ultrasonographic examinations were daily performed from 15 days after ovulation until parturition to determine the time of first detection and ultrasonographic appearance of the fetal and extra-fetal structures in pregnant 10 Maltese, 10 Yorkshire Terrier, 15 Shih-tzu, and 10 Miniature Schnauzer bitches, respectively. Gestational age was timed from the day of ovulation (day 0), which was estimated to occur when plasma progesterone concentration was first increased above 4.0ng/ml. The gestational length was $63.4{\sim}63.6$ (range: $61{\sim}65$) days and the geatational length was no statistically significant difference among bitches (p>0.05). The initial detection of the extra-fetal structures were; gestational sac at days $18.9{\sim}19.5\;(17{\sim}22)$, zonary placenta at days $24.6{\sim}25.5\;(23{\sim}28)$, yolk sac membrane at days $24.6{\sim}25.5\;(23{\sim}27)$, yolk sac tubular shape at days $26.1{\sim}26.3\;(24{\sim}28)$, and amniotic membrane at days $26.1{\sim}28.2\;(24{\sim}31)$, respectively. The time of the first detection of the extra-fetal structures were no statistically significant difference among bitches (p>0.05). The initial detection of the fetal structures were; embryo initial detection at days $22.5{\sim}22.9\;(21{\sim}24)$, heartbeat at days $23.2{\sim}23.8\;(21{\sim}25)$, embryo bipolar shape $27.6{\sim}28.9\;(26{\sim}30)$, fetal movement at days $31.9{\sim}32.8\;(27{\sim}34)$, limb buds at days $29.1{\sim}30.7\;(27{\sim}33)$, stomach at days $31.1{\sim}33.1\;(29{\sim}34)$, urinary bladder at days $32.4{\sim}33.2\;(29{\sim}35)$, skeleton at days $34.7{\sim}35.9\;(34{\sim}39)$, and kidney at days $42.1{\sim}44.7\;(41{\sim}48)$, respectively. The the time of the first detection of the fetal structures were no statistically significant difference among bitches (p>0.05). These results indicate the evaluation of the time of first detection and ultrasonographic characteristics of the gestational structures might be useful for pregnancy diagnosis, estimating fetal age, embryonic resorption, fetal monster, abnormal fetal growth and fetal viability, respectively.