• Journal of Mechanical Science and Technology
• /
• 제19권7호
• /
• pp.1424-1431
• /
• 2005

In this study, head injury by impact force was evaluated by numerical analysis with 3-dimensional finite element (FE) model. Brain deformation by frontal head impact was analyzed to evaluate traumatic brain injury (TBI). The variations of head acceleration and intra-cranial pressure (ICP) during the impact were analyzed. Relative displacement between the skull and the brain due to head impact was investigated from this simulation. In addition, pathological severity was evaluated according to head injury criterion (HIC) from simulation with FE model. The analytic result of brain damage was accorded with that of the cadaver test performed by Nahum et al.(1977) and many medical reports. The main emphasis of this study is that our FE model was valid to simulate the traumatic brain injury by head impact and the variation of the HIC value was evaluated according to various impact conditions using the FE model.

• 재활간호학회지
• /
• 제14권1호
• /
• pp.62-69
• /
• 2011

Purpose: The study assessed whether nurse staffing was associated with 3 nursing sensitive outcomes used in intensive care unit (ICU) nursing care plans. Methods: This study was a retrospective and descriptive study using clinical data extracted from the data warehouse of a large acute care hospital in the Midwest. One-way analysis of variance was used to analyze the records of 578 ICU patients admitted from March 25 to May 31, 2010. Results: 79 Nursing Outcomes Classification (NOC) outcomes were used in the nursing care plans. The 3 most commonly used NOC outcomes (Pain Level, Infection Severity, and Tissue Integrity: Skin and Mucous Membranes) were analyzed to determine their relationship to nurse staffing. As a nurse staffing ratio, the skill mix of nursing caregivers ranged from 0.74 to 1 with an average of 0.90. This skill mix of nursing caregivers significantly differed among the changes in Infection Severity scores. However, the mean difference was only 0.02. Conclusion: The results did not support that greater nurse staffing was associated with better outcomes. More research is still needed to determine the usefulness of Pain Level, Infection Severity, and Tissue Integrity: Skin and Mucous Membranes in evaluating the impact of nurse staffing.

• 한국자동차공학회논문집
• /
• 제2권2호
• /
• pp.1-11
• /
• 1994

The most commonplace of collisions that directly affect people is that of vehicles. Safety studies have noted a correlation between vehicle occupant injury severity and velocity changes. Methods for estimating collision velocity changes are discussed here. This topic is part of what is referred to as accident reconstruction. Only planar collisions are considered. When a vehicle collides with another, impact dynamics with friction should be considered. This paper presents a general analysis methodology of impact. must dynamics incorporating friction. The presence of friction between sliding contacts during the impact makes the problem difficult since the events such as reverse sliding or sticking, which may occur at different times throughout the impact, must be determined. This paper uses the results of RICSAC experiments for verifying the developed methodology. The analysis and experimental results agree well.

• 한국방재학회:학술대회논문집
• /
• 한국방재학회 2008년도 정기총회 및 학술발표대회
• /
• pp.629-632
• /
• 2008

Risk-based security impact evaluation may be affected by various factors according to numerous combinations of explosive devices, cutting devices, impact vehicles, and specific attack location to consider. Presently, in planning and design phases, designers are still often uncertain of their responsibility, lack of information and training of security. Therefore, designers are still failing to exploit the potential to reduce threats on site. In this study, the concept of security impact assessment is introduced in order to derive the performing design for safety in design phase. For this purpose, a framework for security impact assessment model using risk-based approach for bridge structures is suggested. The suggested model includes of information survey, classification of terror threats, and quantitative estimation of severity and occurrence.

• 한국안전학회지
• /
• 제32권6호
• /
• pp.143-149
• /
• 2017

According to traffic accidents statistics, the number of fatalities, injuries and the rate of increase of traffic accidents have been decreasing over last 5-years. The fatality rate is 1.9 for total accidents but the fatality rate for single vehicle accidents shows a 7.9, which is 4 times greater than the average for all accidents. Single vehicle accidents, usually occur as a vehicle impacts a fixed objects on the roadside as the vehicle runs-off from the road. However, few researches have been conducted considering the accident severity of single vehicle accidents which impact to the fixed objects on the road. The single vehicle accident is directly related to the composition of road cross section, (since it is the required the minimum width of a road for all run-off-the-road vehicles to recover or come to a safe stop). Therefore, this study analyzes the influence of road cross section on traffic accidents to find out the severity of single vehicle accident. To analyze the road elements which are related to the accident severity, the Ordered Probit Model was used. As variables, the element of road cross section such as the radius(m), vertical curve(%), cross sectional grade(%), road width(m). number of climbing lane, median, and curb, were used (as was the 3-years of accidents data). This study found out that cross slope(%), road width(m), and the number of climbing lane are related to the severity of accident. The result of this study could be expected to improve the road safety and to be used as the base data for further road safety research.

• 대한토목학회논문집
• /
• 제39권3호
• /
• pp.391-398
• /
• 2019

일반적으로 화물차 사고는 일반 승용차 사고 대비 심각도가 높은 것으로 알려져 있으며, 최근 국내 화물차 사고 발생건수 및 사망률은 지속적으로 증가하고 있는 추세이다. 그러나 국내 화물차 사고 심각도 관련 연구는 매우 제한적으로 수행되었다. 이러한 배경 하에 본 연구는 국내 고속도로에서 과거 6년간 발생한 화물차 사고 심각도를 분석하여 화물차 사고 심각도에 영향을 미치는 인자를 도출하고자 한다. 분석을 위해 순서형 프로빗 모형이 적용되었으며 총 10개의 주요 인자가 도출되었다. 이중 8개 인자(나이가 많을수록, 졸음운전의 경우, 추돌 사고의 경우, 사고 후 전도나 전복이 된 경우, 사고 후 화재가 발생한 경우, 사고에 포함된 차량 수가 많을수록, 충돌 속도가 높을수록, 야간주행(0-6시)에 발생한 사고의 경우)는 사고 심각도가 높아지는 것으로, 2개 인자(눈이 오는 경우, 단독차량사고의 경우)는 감소시키는 것으로 나타났다. 본 연구 결과는 국내 고속도로 화물차 사고 심각도를 낮추기 위한 정책 수립 시 기반 자료로 활용할 수 있을 것으로 기대된다.

• The Korean Journal of Pain
• /
• 제35권3호
• /
• pp.327-335
• /
• 2022

Background: The pathophysiology of fibromyalgia (FM) involves many mechanisms including central nervous system sensitization theory, autonomic nervous system (ANS) dysfunction, and recently small fiber neuropathy. While the small fiber neuropathy itself can cause ANS dysfunction and neuropathic pain (NP), it is still unknown whether ANS problems have an association with severity of disease and NP in patients with FM. The aim of this study was to evaluate ANS dysfunction in FM patients and to explore possible associations of ANS dysfunction with disease severity and NP. Methods: Twenty-nine FM patients and 20 healthy controls were included in this cross-sectional study. Participants were tested using sympathetic skin responses (SSR) and R-R interval variation analyses for sympathetic and parasympathetic ANS dysfunction, respectively. Disease severity and somatic symptoms of patients with FM were evaluated using the ACR-2010 scales and Fibromyalgia Impact Questionnaire, and NP symptoms were evaluated using the Pain Detect Questionnaire and Douleur Neuropathique questionnaire. Results: FM patients were found to have ANS dysfunction characterized by increased sympathetic response and decreased parasympathetic response. SSR amplitudes were found to be correlated with a more severe disease. Although nonsignificant, NP severity tended to be associated with a decrease in sympathetic and parasympathetic activities. Conclusions: ANS dysfunction may play a role in the pathophysiology of FM. The trend of decreased ANS functions in FM patients exhibiting NP contradicts the notion that FM is a sympathetically maintained NP and may be explained with small fiber involvement.

• 한국재난정보학회 논문집
• /
• 제20권2호
• /
• pp.440-447
• /
• 2024

연구목적: 국내의 차량 등록 대수는 계속 증가하고 있다. 삶의 질 향상으로 인한 교통량 또한 점진적으로 증가하므로 사고 심각도가 증가 및 혼잡문제 또한 야기될 것으로 예상된다. 따라서, 첨두 교통사고와 비첨두 교통사고의 사고 요인을 분석할 필요가 있다고 판단된다. 연구방법:인천광역시의 첨두 및 비첨두 교통사고의 심각도를 첨두와 비첨두로 나누어 분석하여 사고에 영향을 미치는 요인을 알아보고자 한다. XGBoost 머신러닝 기법을 적용하여 첨두 및 비첨두 교통사고 심각도를 분석하였으며 결과를 통하여 plot으로 시각화하였다. 연구결과:첨두시 피해운전자 차종_승합인 경우 등 비 첨두시는 피해운전자 차종_건설기계 등이 사고 심각도를 높이게 되는 변수인 것으로 분석되었다. 결론: 첨두와 비첨두 사고 심각도의 요인을 도출한 것에 의의가 있고 추후 첨두 및 비첨두시의 사고 심각도를 낮추고 국내 교통의 혼잡 요인을 분석하여 혼잡 비용을 줄일 수 있는 것에 활용되기를 바란다.

• Structural Engineering and Mechanics
• /
• 제82권2호
• /
• pp.233-244
• /
• 2022

Following a loss of control, the impact against a road barrier in a turn predominates among the most severe motorcyclist accidents. These road restraint devices can be equipped with a motorcycle screen, the function of which is to restrain the rider and minimize the consequences of the impact in terms of the severity of injuries. The performance of these screens is evaluated by the European normative procedure EN1317-8, which specifies the test conditions, based on one or two configurations. In practice, however, these impact conditions are very diverse, difficult to extrapolate from accident analysis and therefore poorly investigated. This study is interested in improving knowledge of these impact conditions in terms of impact speed, impact angle and particularly position of the rider. A finite element model has been developed to simulate the dynamic behavior of the rider from loss of control to impact on the screen. Statistical analysis of the results shows a high variability of the impact conditions, in particular with regard to the direction of turn (to the right or to the left). Some improvements are suggested in order to overcome the limitations inherent in standard procedures.

• 한국자동차공학회논문집
• /
• 제4권6호
• /
• pp.85-96
• /
• 1996

Most protection systems such as seat belts and airbags are not effective means for side structure. There has been significant effort in the automobile industries in seeking other protective methods, such as stiffer structure and padding on the door inner panel. Therefore, a car-to-car side impact model has been developed using ATB occupant simulation program and validated for test data of the vehicle. Compared to the existing side impact models, the developed model has a more detailed vehicle side structure representation for the more realistic impact response of the door. This model include impact bar which effectively increases the side structure stiffness without reduction of space between the occupant and the door and padding for absorbing impact energy. The established model is applied to a 4-door vehicle. The parameter study indicated that a stiffer impact bar would reduce both the acceleration-based criteria, such as thoracic trauma index: TTI(d), and deformation-based criteria, such as viscous criterion(VC). Padding on the door inner panel would reduce TTI(d) while VC gives the opposite indication in a specified thickness range. For a 4-door vehicle, the stiffness enhancement of B-pillar is more beneficial than that of A-pillar for occupant injury severity indices.