• Journal of the Korea Society for Simulation
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• v.26 no.3
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• pp.1-11
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• 2017

Blast injuries in a compartment are investigated, and the effects of obstacles on blast injury are particularly analyzed by comparing injuries in the compartments with or without protruding obstacles inside. Even if blast pressure profile tends to be complicated in a confined space unlike in open field, it can be obtained in a relatively short time by using some empirical fast running models for simple confined spaces. However, a finite element method should be employed to obtain blast pressure profiles in a case with obstacles in confined spaces, because the obstacles heavily disturb blast waves. On the other hand, Axelsson SDOF(Single degree of freedom) model and ASII(Adjusted severity of injury index) injury level are employed to estimate blast injury in compartments, because the usual pressure-impulse injury criterion based on the ideal Friedlander waves in open the field cannot be applied to personnel in a confined space due to complexity of blast waves inside. In cases with obstacles, chest wall velocity was reduced by 26 to 76 percent(%) and the personnel injury in the compartment caused by blast was also reduced.

• Journal of Auto-vehicle Safety Association
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• v.3 no.2
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• pp.34-41
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• 2011

Side collisions (or side crash) account for 51.6% of all car to car accidents occurred in 2010. It is necessary to analyze those vehicles' structure deformation and passengers' injuries in the side collisions. A moving barrier (950kg) is currently used in the KNCAP side impact test. However, in order to enhance a passengers' safety in the side collisions, we introduce an AE-MDB (1500kg) which provides more severe conditions for this test. In this study, the test results using both barriers are compared and analyzed.

• Journal of Chest Surgery
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• v.6 no.2
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• pp.189-194
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• 1973

A cardiac injury is one of the most dramatic and demanding emergencies than may be cared by the surgeon. Four patients who sustained penetrating wound of the heart have been experienced in the Depart-ment of Thoracic Surgery, Kyungpook National University Hospital. They were 3 males and one female. The age was between 21 and 25. All of this series had stab wounds on the heart by instruments of scissors, gimlet, kitchen knife and glass. Injured sites were two cases of right ventricle, one of the right atrium and one of indifinitive with pericardial laceration. Three of these patients have been successfully treated by emergency thoracotomy with 3-0 silk sutures for myocardial penetrating wounds. One of these patients occurred cardiac arrest during surgery and expired, who was in penetrated right ventricular injury through which massive bleeded. The classic clinical description of tamponade, Beck`s triad, seemed to be useful for making diagnosis of the tamponade but not entirely reliable as diagnostic criterion of the tamponade. In the studing of 3 tamponade cases in these series, the triad of Beck was presented in only two cases. Elevated venous pressure was thought to be a valuable diagnostic factor in pericardial tamponade.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.10a
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• pp.130-137
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• 1997

During crash of a vehicle a major part of the kinetic energy of the driver is absorbed by a steering system. The deformation characteristics of the steering system has significant effects on the injury of the driver. A part of the energy is absobed by the steering wheel and another part by the collapsable steering column. It is believed that the structure of the steering wheel has an important effect on the injury of the driver. A design criterion is suggested for steering wheels for maximum protection of drivers. Taguchi method is used to obtain the effects design parameters.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.5
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• pp.130-140
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• 1999

During crash of a vehicle, most of the kinetic energy of the driver is absorbed by the steering system. The deformation characteristics of the steering system has significant effects on the injury of the driver. A part of the energy is absorbed by the steering wheel and another part by the collapsable steering column. It is believed that strength distribution between the wheel and the column has an important effect on the injury of the driver. A design criterion is suggested for steering wheels for maximum protection of drivers. Tagushi method is used to analyse the effects of design parameters.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1047-1048
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• 2013

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.3
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• pp.537-547
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• 2001

The paper proposes the fuzzy logic global approximate optimization strategies in optimal sizing of automotive A-pillar trim with rib structures for occupant head protection. Two different strategies referred to as evolutionary fuzzy modeling (EFM) and neuro-fuzzy modeling (NFM) are implemented in the context of global approximate optimization. EFM and NFM are based on soft computing paradigms utilizing fuzzy systems, neural networks and evolutionary computing techniques. Such approximation methods may have their promising characteristics in a case where the inherent nonlinearity in analysis model should be accommodated over the entire design space and the training data is not sufficiently provided. The objective of structural design is to determine the dimensions of rib in A-pillar, minimizing the equivalent head injury criterion HIC(d). The paper describes the head-form modeling and head impact simulation using LS-DYNA3D, and the approximation procedures including fuzzy rule generation, membership function selection and inference process for EFM and NFM, and subsequently presents their generalization capabilities in terms of number of fuzzy rules and training data.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.5
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• pp.81-87
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• 2012

New car assessment program (NCAP) originated from USNCAP in 1979 has been implemented in several countries or markets, for instance USA, Europe, Korea, Japan, China and Australia. NCAP has contributed greatly to reduce accidental tolls. But recently, NCAP performance has no distinction between cars because manufacturer have been continuously developed to improve NCAP performance. Therefore, NHTSA announced new USNCAP protocol becoming effective from MY2011. NHTSA had carried out many NCAP tests based on the new test protocol and announced these test results. In this paper, USNCAP test results were reviewed by statistical method. This review was focused on passenger cars and frontal crash test results in order to investigate effect of changes in new NCAP protocol. There are two key changes, one is sited female dummy in passenger position, the other is enlarged to 4 scoring body regions in each dummy. Results of this review were summarized as followings. Performance in Passenger (12.5%) is lower than Driver's (50%) for number of 5 star vehicle. Neck injury criterion is dominant to NCAP star rating for both dummies in the mean sense. For standard deviation, chest deflection is showed largest value in driver dummy but neck injury criterion is showed for passenger's. DKAB and PKAB were equipped 28.1% and 6.2%, respectively. Consequently, the countermeasure for new USNCAP frontal crash test is essential to control well dummy kinematics with some safety features including KAB to reduce neck injuries.

• The Korean Journal of Nuclear Medicine
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• v.37 no.2
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• pp.103-109
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• 2003

Purpose: In patients with chronic knee pain, the diagnostic performance of $^{99m}Tc-MDP$ knee SPECT for internal derangement of knee is deteriorated due to degenerative changes. In this study, we tried to establish diagnostic criteria to differentiate medial meniscal injury (MMI) from degenerative change (DC) when the uptake is increased in medial compartment. Materials and Methods: A total of 49 knee SPECT of the patients with chronic (more than 3 months) knee pain, which showed increased $^{99m}Tc-MDP$ uptake in the medial compartment, were included in this study. The diagnosis was confirmed by arthroscopy. On knee SPECT, 3 diagnosic criteria for MMI were investigated. In Criterion I, MMI was diagnosed when crescentic uptake was observed in the medial tibial plateau. In Criterion II, crescentic uptake was further classified into anterior, mid, posterior, and diffuse patterns, according to the location of maximal uptake; and only crescentic mid, posterior, and diffuse patterns were diagnosed as MMI. In Criterion III, MMI was diagnosed when medial tibial plateau showed higher activity then medial femoral condyle. The diagnostic performance of the 3 criteria was compared. Results: The sensitivity and specificity were 93% and 14% in Criterion I, 89% and 38% in Criterion II, and 75% and 67% in Criterion III, respectively. Criterion III had significantly improved diagnostic performance, especially, specificity. Conclusion: In this study, we established a practical diagnostic criterion to differentiate MMI from DC on knee SPECT. The result is helpful to improve the diagnostic value of knee SPECT as a screening test for chronic knee pain.

• Journal of the Korea Society of Computer and Information
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• v.28 no.7
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• pp.95-102
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• 2023

The purpose of this study was to investigate the effect of 8 weeks of core training on dynamic posture control, lower extremity injury and proprioceptive joint position sensory in ski athletes. Twenty subjects participated in this study and were randomly divided into two groups : exercise group (Ex=10) and control group (Con=10). The core training program consisted of a bench, a sideways bench, a plank, a side bridge, and a supine bridge, and was conducted three times a week for 8 week. The dynamic posture control had a significant effect on the left and right postero-medial reach, and the lower extremity criterion test had a significant effect on the left and right composite scores. In addition, there was a significant decrease in the proprioceptive joint position sense at 15°of the left leg and 45°. In conclusion, 8 weeks a core training have been shown to improve skiers' dynamic posture control, lower extremity injury and proprioceptive joint position sensory.