• 방송공학회논문지
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• 제26권2호
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• pp.132-142
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• 2021

본 연구는 실생활에서 가장 많이 접할 수 있는 모바일 전면 카메라를 이용하여 심장박동, 심장박동 변이율, 산소포화도, 호흡도, 스트레스수치, 혈압을 측정할 수 있는 효과적인 방법론을 제시하는 것이 목적이다. Blaze Face를 이용하여 실시간으로 얼굴인식을 진행하여 안면 이미지 데이터를 취득하고 눈, 코 입, 귀의 특징 점을 이용하여 이마를 관심영역으로 지정하며 평균값을 시간 축으로 정렬한 후 생체징후 측정에 이용하였다. 생체징후 측정 기법은 fourier transform을 기본으로 이용하였으며, 측정하고자 하는 생체징후에 맞게 노이즈 제거 및 필터 처리함으로써 측정값의 정확도를 향상 시켰다. 결과를 검증하기 위해 접촉식 센서와 비접촉식 센서 비교를 진행하였다. 분석 결과 안면 이미지를 이용하여 심장박동, 심장 박동 변이율, 산소포화도, 호흡도, 스트레스, 혈압 총 여섯 가지 생체 징후를 추출 할 수 있는 가능성을 확인하였다.

• 한국국방경영분석학회지
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• 제25권2호
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• pp.106-116
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• 1999

The purpose of this study is to present a method for determining the k most vital arcs in the maximum flow problem using genetic algorithms. Generally, the problem which determine the k most vital arcs in maximum flow problem has known as NP-hard. Therefore, in this study we propose a method for determining all the k most vital arcs in maximum flow problem using genetic algorithms. First, we propose a genetic algorithm to find the k most vital arcs removed at the same time and then present the expression and determination method of individuals compatible with the characteristics of the problem, and specify the genetic parameter values of constitution, population size, crossover rate, mutation rate and etc. of the initial population which makes detecting efficiency better. Finally, using the proposed algorithms, we analyzed the performance of searching optimal solution through computer experiment. The proposed algorithms found all alternatives within shorter time than other heuristic methods. The method presented in this study can determine all the alternatives when there exists other alternative solutions.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제48권6호
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• pp.348-355
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• 2022

Objectives: To compare the vital sign stability and cost of two commonly used sedatives, midazolam (MDZ) and dexmedetomidine (DEX). Patients and Methods: This retrospective study targeted patients who underwent mandibular third molar extractions under intravenous sedation using MDZ or DEX. The predictor variable was the type of sedative used. The primary outcome variables were vital signs (heart rate and blood pressure), vital sign outliers, and cost of the sedatives. A vital sign outlier was defined as a 30% or more change in vital signs during sedation; the fewer changes, the higher the vital sign stability. The secondary outcome variables included the observer's assessment of alertness/sedation scale, level of amnesia, patient satisfaction, and bispectral index score. Covariates were sex, age, body mass index, sleeping time, dental anxiety score, and Pederson scale. Descriptive statistics were computed including propensity score matching (PSM). The P-value was set at 0.05. Results: The study enrolled 185 patients, 103 in the MDZ group and 82 in the DEX group. Based on the data after PSM, the two samples had similar baseline covariates. The sedative effect of both agents was satisfactory. Heart rate outliers were more common with MDZ than with DEX (49.3% vs 22.7%, P=0.001). Heart rate was higher with MDZ (P=0.000). The cost was higher for DEX than for MDZ (29.27±0.00 USD vs 0.37±0.04 USD, P=0.000). Conclusion: DEX showed more vital sign stability, while MDZ was more economical. These results could be used as a reference to guide clinicians during sedative selection.

• 국제물리치료학회지
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• 제2권2호
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• pp.339-343
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• 2011

The purpose of this study is to see the effect of functional electrical stimulation on forced vital capacity and alternating motion rate in children with spastic cerebral palsy. This study divided 20 children with spastic cerebral palsy into two groups; functional electrical stimulation treatment group and control group. Functional electrical stimulation treatment group had 20min per day treatment three times a week for four weeks and the control group did not have any treatment. Before and after intervention, this study measured forced vital capacity and alternate motion rate(/peo/,/teo/) for all children. Forced vital capacity showed statistically significant increase for the group with functional electrical stimulation(p<.05) while the control group did not show any significant increase(p>.05). Alternate motion rate showed statistically significant increase for the group with functional electrical stimulation(p<.05) while the control group did not show any significant increase(p>.05). This result shows that functional electrical stimulation affected the ability of the children with spastic cerebral palsy who have decreased breathing and phonation capability.

• 대한간호학회지
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• 제17권2호
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• pp.137-144
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• 1987

The main purpose of this study was to examine the validity of the vital sign as an instrument of stress reaction measurement. From July to August 1986, stress reaction was evaluated by the difference of endoscopic vital sign on 93 G-I troubled out-patients who underwent endoscopy for the first time and did not have any evidence of cardiovascular disease. The data were analysed by x$^2$-test, Paired . t-test, ANCOVA and Multiple Comparison Test. The result of study were as follows: 1. The frequency of gastric disease was differed by the family type, and the mobility of gastritis and gastric cancer were more increased in nuclear family than in large family (p=0.019). 2. In a comparison of before with after 5 minutes endoscopic vital sign, and a Pulse rate (P=0.0001), respiration rate (p=0.0001), systolic blood pressure (p=0.0002) and diastolic blood Pressure (P=0.006) were significantly increased after 5minutes by endoscopy in contrast with before 5minutes. 3. The control of before 5 minutes of endoscopic vital sign, after 5 minutes of endoscopic systolic (p=0.024) and diastolic blood pressure (p=0.0146) were more elevated in biopsyed group than in non-biopsyed, group. And after 5minutes of endoscopic respiration rate was more increased in gastric cancer than in gastritis (p=0.0406) or gastric ulcer (p=0.0073). And after 5 minutes of endoscopic systolic blood pressure was elevated over 50years old men (P=0.0238). In short, the increase of a pulse rate af ter 5 minutes of endoscopy was not influenced by general characteristics of samples in this experiment. And systolic blood pressure over 50years old men must be considered of physiological hypertension.

• 대한임베디드공학회논문지
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• 제18권6호
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• pp.277-283
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• 2023

Vital signals provide essential information regarding the health status of individuals, thereby contributing to health management and medical research. Present monitoring methods, such as ECGs (Electrocardiograms) and smartwatches, demand proximity and fixed postures, which limit their applicability. To address this, Non-contact vital signal measurement methods, such as CW (Continuous-Wave) radar, have emerged as a solution. However, unwanted signal components and a stepwise processing approach lead to errors and limitations in heart rate detection. To overcome these issues, this study introduces an integrated neural network approach that combines noise removal, demodulation, and dominant-frequency detection into a unified process. The neural network employed for signal processing in this research adopts a MLP (Multi-Layer Perceptron) architecture, which analyzes the in-phase and quadrature signals collected within a specified time window, using two distinct input layers. The training of the neural network utilizes CW radar signals and reference heart rates obtained from the ECG. In the experimental evaluation, networks trained on different datasets were compared, and their performance was assessed based on loss and frequency accuracy. The proposed methodology exhibits substantial potential for achieving precise vital signals through non-contact measurements, effectively mitigating the limitations of existing methodologies.

• 한국전자파학회논문지
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• 제30권5호
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• pp.418-426
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• 2019

최근 사물인터넷(internet of things: IoT) 스마트 홈 시스템과 관련하여 레이다 기반의 다양한 생체신호 탐지 기법들이 개발되고 있다. 생체신호는 폐에 의한 호흡수와 심장에 의한 심장박동수로 정의되며, 이는 일반적으로 흉부 또는 등의 미세한 움직임을 야기한다. 이때, 이 미세한 움직임은 레이다 수신신호의 위상을 변화시키기 때문에, 생체신호는 주로 위상 변화에 대한 스펙트럼 분석을 통해 탐지된다. 하지만, 호흡수와 달리 심장박동수에 의한 위상 변화는 매우 미약하기 때문에 실제 측정환경에서는 다양한 원인들로 인해 심장박동수가 오탐지될 확률이 매우 높다. 따라서 본 논문에서는 먼저 생체신호 오탐지를 야기하는 원인들을 분석한 후, 이를 바탕으로 효과적인 생체신호 탐지 기법을 제안한다. 제안된 기법은 크게 1) 위상 분리, 2) 위상 미분 및 필터링, 3) 생체신호 탐지, 그리고 4) 오탐지율 감소 단계로 구성되며, IR-UWB(Impulse-Radio Ultra-Wideband)를 사용한 실험 결과에서 보다 효율적이고 정확하게 생체신호가 탐지됨을 확인할 수 있었다.

• 성인간호학회지
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• 제21권2호
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• pp.141-154
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• 2009

Purpose: The purpose of this study was to compare the difference of change in oxygen saturation, vital signs and suction time taken for the suctioning during endotracheal suctioning performed with closed suction system and with opened suction system. Methods: Data were collected from 31 adult patients with ventilator treatment who were admitted to a university hospital in Seoul and the collection period was from July 1 to November 15, 2005. Oxygen saturation, heart rate, respiration rate and mean arterial pressure were collected immediately prior to the suctioning intervention, during and 1 and 5 minutes after the suctioning from opened suction system and closed suction system. Results: 1) The difference in oxygen saturation was statistically significant in recovery time for oxygen saturation to return to baseline values after suctioning was significantly rapid on closed suction system (p<.05). 2) The difference in heart rate, respiration rate and mean arterial pressure was statistically insignificant 3) The suction time was shorter in closed suction system. Conclusion: Closed suction system is more efficient, as compared with the open suction system in the ventilator treatment.

• 한국인구학
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• 제3권1호
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• pp.52-61
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• 1979

The purpose of the study is to construct a life table for population. It is based on the fraction of last year of life, $a_X$. The data necessary for this purpose have been obtained from the 1975 Population Census Report of Korea and the Vital Statistics of Shindong-myon, Chunseong-gun, Gangwon Province which is collected for the Seoul National University public health program. Age specific death rate is adapted by the Model Life Table, West, Level 21. For the age groups of less than 5 years of age, when the record of vital events can be obtained, the fractions are calculated from the community vital statistics. And for the age groups older than 5 years of age, Greville's Method is used. The findings are summarized as follows: 1) The fraction of last year of life in infantile group is 0.3684 for males, 0.3711 for females, and in 1-4 years of age group 1.2164 for males, 1.2274 for females. Both are more than those of Japan and U.S. in 1963. 2) Infant mortality rate is 42.37 for males, 31.77 for females per 1,000 live births. 3) The mortality curves show that a higher rate is observed under 1 year of age. It drops to the lowest point at around 10 years of age and rises again as the age increases. 4) The age estimated half-survival rate is during the age group of 70-74 for both sexes. 5) Life expectancy at the age of 0 shows 65.73 years for males and 69.22 years for females.

• 한국의료질향상학회지
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• 제11권1호
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• pp.4-14
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• 2004

Background : To examine the problems involved in writing practice of death certificates, we compared the determination of underlying cause of death for vital statistics using recorded underlying cause of death in issued death statistics. Methods : We collected 688 mortality certificates issue in year of 2,000 from 3 university hospitals. And we also collected vital statistics from ministry of statistics. The causes of death were coded by experienced medical record specialists. And causes of death determined at ministry of statistics for national vital statistics were mapped to causes of death recorded at each death certificates. The rate that underlying causes of death for vital statistics were derived from underlying causes of death recorded at issued death certificates were analysed. Results : 64.5% of underlying cause of death for could be derived from underlying cause of death recorded at issued death certificates, 8.6% derived from intermediate cause of death, and 3.9% derived from direct cause of death. In 23% of cases, underlying cause of death could not be derived using issued death certificates. The rate that underlying cause of death for vital statistics could be derived from underlying cause of death recorded at death certificates was different between 3 university hospitals. And the rate was also different between death certificates and postmortem certificates. We classified the causes of death using 21 major categories. The rate was different between diseases or conditions that caused death too. Conclusion : When we examined the correctness of death certificate writing practice using above methods, correctness of writing could not be told as satisfactory. There was difference in correctness of writing between hospitals, between death certificates and postmortem certificates, and between diseases and conditions that caused death. With this results, we suggested some strategy to improve the correctness of death certificate writing practice.