• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.331-342
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• 2005

This paper presents a non-destructive evaluation (NDE) technique for detecting damages on a jointed steel plate on the basis of the time of flight and wavelet coefficient, obtained from wavelet transforms of Lamb wave signals. Support vector machines (SVMs), which is a tool for pattern classification problems, was applied to the damage estimation. Two kinds of damages were artificially introduced by loosening bolts located in the path of the Lamb waves and those out of the path. The damage cases were used for the establishment of the optimal decision boundaries which divide each damage class's region from the intact class. In this study, the applicability of the SVMs was investigated for the damages in and out of the Lamb wave path. It has been found that the present methods are very efficient in detecting the damages simulated by loose bolts on the jointed steel plate.

• Wind and Structures
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• v.15 no.2
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• pp.147-162
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• 2012

Argentina is a large country with several areas dominated by different climate mechanisms. Since 2008, damage to civil structures caused by strong winds has been surveyed in Chaco and the neighbouring areas. Chaco is a province of NEA, the north-east region of the Argentina, which also includes the provinces of Formosa, Corrientes and Misiones. The strong wind events in NEA are related to severe convective storms. In this work, we present findings about wind-induced damage in NEA and the prevailing meteorological conditions. We emphasise seven particular cases for which the conditions of the atmosphere were reconstructed through reanalysis.

• Journal of Aerospace System Engineering
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• v.2 no.2
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• pp.1-7
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• 2008

Recently the wind energy has been alternatively used as a renewable energy resource instead of the mostly used fossil fuel due to its lack and environmental issues. This work is to propose a structural design and analysis procedure for development of the low noise 100W class small wind turbine system which will be applicable to relatively low speed region like Korea and for the domestic use. Structural analysis including load cases, stress, deformation, buckling, vibration and fatigue life was performed using the Finite Element Method, the load spectrum analysis and the Miner rule. In order to evaluate the designed structure, the structural test was carried out and its test results were compared with the estimated results. In addition, the blade should be safe from the impact damage due to FOD(Foreign Object Damage) including the bird strike. In order to analize the bird strike penomena on the blade, MSC. Dytran was used, and the applied method Arbitrary Lagrangian-Eulerian was evalud by comparison with the previous study results.

• Structural Engineering and Mechanics
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• v.35 no.3
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• pp.365-377
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• 2010

In the present article, effect of non-uniform excitation due to spatially variation of seismic input on nonlinear response of concrete gravity dams is considered. The reservoir is assumed compressible. Isotropic damage mechanics approach is used to model static and dynamic nonlinear behavior of mass concrete in 2D space. The validity of utilized nonlinear model is considered using available theoretical results under static and dynamic conditions. The tallest monolith of Pine Flat dam is selected as a case study. Two cases are analyzed for considering the effect of limited wave propagation velocity on seismic behavior of the dam-reservoir system in which travelling velocities are chosen as 2000 m/s and infinity. It is found that tensile damage in neck and toe regions and also, in the vicinity of the base increase when the system is excited non-uniformly.

• The Journal of the Korea Contents Association
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• v.17 no.4
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• pp.267-274
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• 2017

The natural disasters such as typhoon, earthquake, flood, heavy rain, drought, sweltering heat, wind wave, tsunami and so on, are difficult to estimate the scale of damage and spot. Also, these disasters were being damaged to human life. However, if based on the disaster statistics the past damage cases are analyzed and the estimated damages can be calculated, the initial damage action can be taken immediately and based on the estimated damage scale the damage can be mitigated. In the present study, therefore, we proposed the functions of wind wave damage estimation for the southern coast. The functions are developed based on Disaster Report('91~'14) for wind wave and typhoon disaster statistics, regional characteristics and observed sea weather.

• Structural Engineering and Mechanics
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• v.33 no.2
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• pp.113-136
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• 2009

The seismic induced interaction between multistory structures with unequal story heights (inter-story pounding) is studied taking into account the local response of the exterior beam-column joints. Although several parameters that influence the structural pounding have been studied sofar, the role of the joints local inelastic behaviour has not been yet investigated in the literature as key parameter for the pounding problem. Moreover, the influence of the infill panels as an additional parameter for the local damage effect of the joints on the inter-story pounding phenomenon is examined. Thirty six interaction cases between a multistory frame structure and an adjacent shorter and stiffer structure are studied for two different seismic excitations. The results are focused: (a) on the local response of the critical external column of the multistory structure that suffers the hit from the slab of the adjacent shorter structure, and (b) on the local response of the exterior beam-column joints of the multistory structure. Results of this investigation demonstrate that the possible local inelastic response of the exterior joints may be in some cases beneficial for the seismic behaviour of the critical column that suffers the impact. However, in all the examined cases the developing demands for deformation of the exterior joints are substantially increased and severe damages can be observed due to the pounding effect. The presence of the masonry infill panels has also been proved as an important parameter for the response of the exterior beam-column joints and thus for the safety of the building. Nevertheless, in all the examined inter-story pounding cases the presence of the infills was not enough for the total amelioration of the excessive demands for shear and ductility of the column that suffers the impact.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.461-466
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• 2005

Despite the major advances in the microvascular surgery with success rates of up to 98%, failure and vascular complications still remain even in the experienced hands. Failure of blood to flow across an anastomosis is usually caused by three factors: (1) Technical errors; (2) Undetected damage more proximally or via vasospasm; or (3) A clot or a thrombus. The success of a microvascular surgery depends on the severity of the vascular injury and, proper debridement of an injured vessel, and the failure rate of microvascular anastomosis in cases of trauma is higher as the thrombogenic possibility is increased by the endothelial damage. From January to November in 2003, 460 patients were underwent microvascular surgery(270 replantations and 190 free flap transfers) and re-operations were performed in 15 cases. Cases were reviewed by clinical and operative records. In these cases, causes of post-operative circulation insufficiency were identified as 9 vascular spasms and 6 thromboses at the previous anastomotic site. The average of re-operative success rate was 73%(60% in replantations and 100% in free flaps). In conclusion, through precise postoperative monitoring and assessment, immediate surgical re-exploration could be performed when a vascular complication is suspicious, the success rate of microvascular surgery would be increased more.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.410-417
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• 2004

Fever is a rise in body temperature from any of a variety of causes. One might even feel a fever when body temperature is normal. An imbalance of Yin and Yang due to exogenous pathogenic factors or internal damage is usually considered the cause of fever in Oriental Medicine. Fever from deficiency of Qi is one of the major components of the theory of fever due to internal damage. Clinically, such cases are usually encountered along with wasting diseases and fever does not run high. The compliment of Qi is usually considered the appropriate treatment in these cases. Oriental Medical treatment was performed using herbal medicine after the cause of fever was diagnosed as deficiency of Qi. The herb medicine used in these cases was mainly Bojoongikki-tang(補中益氣湯). Through those treatments good results were seen. More clinical case reports are needed.

• Journal of The Korean Dental Society of Anesthesiology
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• v.10 no.2
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• pp.172-177
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• 2010

Background: Damages of trigeminal nerve, particularly inferior alveolar nerve and lingual nerve, could occur following dental procedures. In some cases, nerve damage may happen as a complication of the local anesthetic injection itself and not of the surgical procedure. Methods: From September 2006 to August 2010, 5 cases of inferior alveolar nerve and lingual nerve damages, which were assumed to happen solely due to local anesthesia, were reviewed. All cases were referred to Division of Oral and Maxillofacial Surgery, Department of Dentistry, Hanyang University Medical Center for legal authentication in the process of criminal procedure. Results: In all five cases, patients complained of altered sensation occurred in the distribution of the inferior alveolar or lingual nerve following block anesthesia. The local anesthetics were 2% lidocaine with 1 : 100,000 epinephrine and the amount of local anesthetics, which were used during injection, were varied. Most of patients experienced the electric stimulation during injection. Recovery was poor and professional supportive care was mostly absent. Conclusions: Dental practitioners should consider that the surgical procedure caused the trigeminal nerve damage, however, dental local anesthesia for inferior alveolar nerve and lingual nerve could be one of the causes for damages. The various mechanisms for nerve damages by local anesthesia are thoroughly discussed.

• The Korean Society of Law and Medicine
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• v.24 no.4
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• pp.3-36
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• 2023

The main issue in medical malpractice civil litigation is medical negligence and the causal relationship between medical negligence and damages. Regarding the presumption of causality in cases where medical negligence is proven, there is a previous Supreme Court decision 93da52402 on February 10, 1995, but it is difficult to find a case that satisfies the textual requirements of the above decision, and yet, in practice, the above decision is cited. In many cases, causal relationships were assumed, and criticism was consistently raised that it was inconsistent with the text of the above judgment. In its ruling, the Supreme Court reorganized and presented a new legal principle regarding the presumption of causality when medical negligence is proven in a civil lawsuit. According to this, If the patient proves ① the existence of an act that is assessed as a medical negligence, that is, a violation of the duty of care required of an ordinary medical professional at the level of medical care practiced in the field of clinical medicine at the time of medical practice, and ② that the negligence is likely to cause damages to the patient, the burden of proving the causal relationship is alleviated by presuming a causal relationship between medical negligence and damage. Here, the probability of occurrence of damage does not need to be proven beyond doubt from a natural scientific or medical perspective, but if recognizing the causal relationship between the negligence and the damage does not comply with medical principles or if there is a vague possibility that the negligence will cause damage, causality cannot be considered proven. Meanwhile, even if a causal relationship between medical negligence and damage is presumed, the party that performed the medical treatment can overturn the presumption by proving that the patient's damage was not caused by medical negligence. Meanwhile, unlike civil cases, the standard is 'proof beyond reasonable doubt' in criminal cases, and the legal principle of presuming causality does not apply. Accordingly, in a criminal case of professional negligence manslaughter that was decided on the same day regarding the same medical accident, the case was overturned and remanded for not guilty due to lack of proof of a causal relationship between medical negligence and death. The above criminal ruling is a ruling that states that even if 'professional negligence' is recognized in a criminal case related to medical malpractice, the person should not be judged guilty if there is a lack of clear proof of 'causal relationship'.