• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.8 s.179
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• pp.2115-2122
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• 2000

The understanding of impact-induced delamination is important in safety and reliability of composite structure. In this study, a model for arrest toughness is proposed in consideration of fracture behavior of composite materials. Also, the probabilistic model is proposed to describe the variability of arrest toughness due to the nonhomogeneity of material. For these models, experiments were conducted on the Carbon/Epoxy composite plates with various thickness using the impact hammer. The elastic work factor used in J-Integral is applicable to the evaluation of energy release rate. The fracture behavior can be described by crack arrest concept and the arrest toughness is independent of the delamination size. Additionally, a probabilistic characteristics of arrest toughness is well described by the Weibull distribution function. A variation of arrest toughness increases with specimen thickness.

• The Korean Journal of Health Service Management
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• v.7 no.1
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• pp.21-34
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• 2013

Hospitals in Korea are enforcing a quality control over 119Emergency Medical Services to increase the survival rate of Out of Hospital Cardiac arrest patients. This study is to analyze the factors that effect the survival rate of Out of hospital Cardiac arrest patients by comparing the results of before and after the quality control enforcement. Cardiac arrest patients can be assorted into pre-decision group and decision group. The study analyzed the survival factors which was based on the adequate use of 119 BLS and ACLS usage rates, response time of 119EMS, qualification of ambulance worker, number of EMS team members, and adequate use of AED according to ECG diagnosis. The analyzation was done over total 1,233 of Cardiac arrest patients from January 1, 2010 to December 31, 2011 After the enforcement of the quality control, the usage of Vital sign check and BLS showed a big difference. Especially, as the usage of ECG showed a significant difference, Shockable rhythm, which is the most important to Cardiac arrest patients, also showed a significant difference. After the enforcement of quality control, the performance of ACLS showed a significant difference in IV. The study showed 119 ambulance workers provided better service in Vital sign and BLS and ACLS after the enforcement of quality control. It is considered a 119 ambulance service effects the survival rate of Cardiac arrest patients. Therefore, it can increase the survival rate and it is necessary to continue a quality control.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.760-766
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• 2014

This study was performed to determine the effect factors in the survival of cardiac arrest patients. This study involved 4,092 cardiac arrest patients of K province, who were transported by 119 during 2010. The data collection involved using 119 rescue daily reports, cardiopulmonary arrest patients emergency treatment detail reports and 119 paramedics survival data. In conclusion, 119 rescue's interventions in the patients with pre-hospital cardiac arrest have significantly increased survival rates. 119 rescue's interventions included early defibrillation, oxygen supply, airway open, and intravenous access affected significantly survival rate. Therefore there is need to increase 119 rescue's interventions performance to improve survival rate of cardiac arrest patients.

• Korean Journal of Adult Nursing
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• v.26 no.5
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• pp.573-583
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• 2014

Purpose: Cardiac arrest has multiple characteristics that need to be approached as an integrated method according to the various changes in the body system. This study was performed to develop a useful guideline for early detection of cardiac arrest by revealing the attributes of cardiac arrest through a concept analysis. Methods: This study was conducted according to the Walker and Avant's concept analysis method. Systematic literature review and in-depth interview with nurses who experienced cardiac arrest situation were conducted. Based on the literature reviews and in-depth interviews with nurses, the attributes and the empirical referents of the concept of cardiac arrest were elicited. Results: The definable attributes of cardiac arrest were 1) loss of consciousness, 2) abnormal respiratory condition, 3) abnormal cardiovascular signs. Cardiac arrest was found to occur by several antecedents such as cardiac problem, non-cardiac problem, or general problem, whereas ischemia and re-perfusion injury, which can lead to multiple organ failure and death, were derived as consequences. Conclusion: In this study, the concept analysis eliciting attributes and empirical referents is found to be useful as a guideline for understanding and managing cardiac arrest. Based on these findings, clinical providers are expected to make a precise and rapid decision on cardiac arrest and respond quickly, which may increase survival rate of the patients underwent the arrest event.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.2
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• pp.42-48
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• 2006

In order to assess the validity of fatigue crack arrest design charts obtained from our previous numerical approach to fatigue crack arrest condition, an extensive fatigue crack growth/arrest test was performed using CT-type integrally stiffened panels. The results are presented as fatigue crack growth rate and non-dimensional crack length relationship, and these are compared with numerically simulated crack growth rates. The measured values of da/dN at the moment of fatigue crack arrest occurred in stiffened panels are good agreement with those numerically simulated crack growth rates.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.4 no.2
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• pp.50-56
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• 2005

To demonstrate the feasibility of utilizing FCAD chart proposed in our previous work, series of crack growth/arrest behavior in the integrally stiffened panels were simulated by numerical method using upper mentioned FCAD charts and a new crack growth rate equation. It is concluded that proposed family of FCAD curves, in the form of non-dimensional arrest load ranges, are reliable indicators of fatigue crack growth/arrest behavior of integrally stiffened panels considered here.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.132-137
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• 2000

In this study, model for arrest toughness is proposed in consideration of fracture behavior of composite materials. Also, the probabilistic model is proposed to describe the variability of arrest toughness due to the nonhomogeneity of material. For these models. experiments were conducted on the Carbon/Epoxy composite plates with various thickness using the impact hammer. The elastic work fatter used in J-Integral is applicable to the evaluation of energy release rate. The fracture behavior call be described by crack arrest concept and the arrest toughness is independent of the delamination size. Additionally, a probabilistic characteristics of arrest toughness is well described by the Weibull distribution function. An increasing of thickness raises a variation of arrest toughness.

• Journal of Chest Surgery
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• v.29 no.1
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• pp.14-23
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• 1996

Circulatory arrest under deep hypothermia is an important auxiliary means for cardiac surgery, especially useful in pediatric patients. However, its clinical safety, particularly with regard to the neurologic outcome after long duration of circulatory arrest, is still not established. This study is a review of the eight years'clinical experience of hypothermic circulatory arrest at the Seoul national University Children's Hospital. During an eight-year period from January 1986 through December 1993, a total of 589 consecutive cardiac operations were done using circulatory arrest under deep hypothermia. Among them, 434 consecutive patients, in whom the duration of arrest was 20 minutes or more, are the subject of this study. The duration of arrest ranged from 20 minutes to 82 minutes (mean = 38.7 minutes) under rectal temperature in the range from 12.5$^{\circ}C$ to 25.8$^{\circ}C$. Early neurologic abnormalities occurred in 47 patients : seizure attacks in 28 patients, motor paralyses with or w thout seizure in 12, blindness in 2, and no recovery of consciousness in 5 patients. The rate of incidence of early neurologic abnormalities was calculated at 15.7%. 25 patients showed late neuropsychologic sequelae, such as motor paralysis (9 patients), recurrent seizures (6), developmental delay (8), and definitely low intelligence (2). The rate of incidence of late neurologic sequelae was 8.5%, By statistical analysis, the following factors were identified as the risk factors for post-arrest neurologic abnormalities ; 1) long duration of circulatory arrest, 2) lower-than-ideal body weight, 3) preexisting neurological abnormalities, 4) associated non-cardiovascular congenital anouialies, and 5) low blood pressure during the early post-arrest period. It is concluded that circulatory arrest under deep hypothermia is a relatively safe means for pediatric cardiac surgery with acceptable risk. However, to warrant maximal safety, it is desirable to limit the duration of arrest to less th n 40 minutes. In addition, it is our contention that the early post-arrest period is a very critical period during which maintenance of adequate perfusion pressure in important for the neurologic outcome.

• The Korean Journal of Emergency Medical Services
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• v.25 no.1
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• pp.205-221
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• 2021

Purpose: This paper is to determine whether automatic defibrillators (AEDs) deployed across communities make a contribution to prevent death in patients with acute cardiac arrest out-of-hospital. Methods: A total of 30,179 cases of cardiac arrest investigation data from the Korea Centers for Disease Control and Prevention was matched to those on emergency medical statistics drawn from annual report for the 2018 Central Emergency Medical Center, and statistics from the National Statistical Office in 2018. Results: Multiple logistic regression analyses revealed that availability of emergency medical resources across associated with different survival rates at emergency room after taking variability of the patient's personal characteristics and episodic situational characteristics held constant. The survival rate was 1.71 times higher for patients living in communities with more than 105 AEDs avaiable per 100,000 inhabitants than for those living in communities with less than 55 AEDs. Conclusion: The survival-related factors of patients with acute cardiac arrest that occurred out-of-hospital were found to be associated with patients' and episodic situational characteristics. The hospital stage were found to be associated with patients characteristics and episodic situational characteristics, The variability of AED available in a community has an impact on survival rate after emergency room treatment.

• The Korean Journal of Emergency Medical Services
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• v.28 no.2
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• pp.47-62
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• 2024

Purpose: This retrospective study analyzed the effects of advanced life support on the recovery of spontaneous circulation (SC) in patients with out-of-hospital cardiac arrest. Methods: The subjects of this study were out-of-hospital cardiac arrest patients transferred to the hospital by 119 paramedics in Gyeongsangbuk-do from January 1, 2021, to December 31, 2022, amounting to a total of 2,524 patients. Results: The younger the age, the higher the probability of recovery of spontaneous circulation, and it was higher when cardiac arrest occurred in a public place or was witnessed. If the patient's initial electrocardiogram rhythm is defibrillable, the probability of recovery from spontaneous circulation is high. The recovery of the spontaneous circulation rate decreased with time between the time of report and the time of contact with the patient. Recovery of the spontaneous circulation rate was high when mechanical chest compression devices and advanced airways were not used. Additionally, this study had positive effects on defibrillation, peripheral intravenous catheter insertion, and epinephrine infusion. Conclusion: Paramedics should actively perform peripheral intravenous catheter insertion and epinephrine infusion, and it should be possible to clearly determine whether defibrillation should be applied through electrocardiographic education.