• Journal of the Society of Naval Architects of Korea
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• v.48 no.1
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• pp.33-41
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• 2011

For the assessment of ultimate longitudinal strengths of damaged hull girders, it is preliminarily necessary to determine the extents and locations of the damages due to severe accidents. This paper deals with the estimation of the damages from collisions and groundings of large-sized vessels where deterministic and probabilistic approaches are investigated. Deterministic damages estimated from MARPOL(or ICLL), ABS and DNV are compared with probabilistic damages from IMO guideline and some references including damage statistic data. Damages from MARPOL show largest one among all the investigated damage estimation, since it was developed not for the residual strength of hull girder but for the damage stability calculation. IMO guideline with high level probability of damage(eg. 95% probability level) also forecasts even severer damage extents than MARPOL. On the other hand, assuming average probability level of damage, the calculated damage sizes are around the one from deterministic approaches.

• Structural Engineering and Mechanics
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• v.41 no.5
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• pp.663-673
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• 2012

A number of mode shape-based structure damage identification methods have been verified by numerical simulations or experiments for on-line structure health monitoring (SHM). However, many of them need a baseline mode shape generated by the healthy structure serving as a reference to identify damages. Otherwise these methods can hardly perform well when multiple cracks conditions occur. So it is important to solve the problems above. By aid of the fractal dimension method (FD), Qiao and Wang proposed a generalized fractal dimension (GFD) to detect the delamination damage. As a modification of GFD, Qiao and Cao proposed the approximate waveform capacity dimension (AWCD) technique to simplify the calculation of fractal and overcome the false peak appearing in the high mode shapes. Based on their valued work, this paper combined and applied the AWCD method and curvature mode shape data to detect multiple damages in beam. In the end, the identification properties of the AWCD for multiple damages have been verified by groups of Monte Carlo simulations and experiments.

• Journal of Advanced Research in Ocean Engineering
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• v.1 no.4
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• pp.239-251
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• 2015

In this study, a spectral fatigue analysis was performed for the topside structure of an offshore floating vessel. The topside structure was idealized using beam elements in the SACS program. The fatigue analysis was carried out considering the wave and wind loads separately. For the wave-induced fatigue damage calculation, motion RAOs calculated from a direct wave load analysis and regular waves with different periods and unit wave heights were utilized. Then, the member end force transfer functions were generated covering all the loading conditions. Stress response transfer functions at each joint were produced using the specified SCFs and member end force transfer functions. fatigue damages were calculated using the obtained stress ranges, S-N curve, wave spectrum, heading probability of each loading condition, and their corresponding occurrences in the wave scatter diagrams. For the wind induced fatigue damage calculation, a dynamic wind spectral fatigue analysis was performed. First, a dynamic natural frequency analysis was performed to generate the structural dynamic characteristics, including the eigenvalues (natural frequencies), eigenvectors (mode shapes), and mass matrix. To adequately represent the dynamic characteristic of the structure, the number of modes was appropriately determined in the lateral direction. Second, a wind spectral fatigue analysis was performed using the mode shapes and mass data obtained from the previous results. In this analysis, the Weibull distribution of the wind speed occurrence, occurrence probability in each direction, damping coefficient, S-N curves, and SCF of each joint were defined and used. In particular, the wind fatigue damages were calculated under the assumption that the stress ranges followed a Rayleigh distribution. The total fatigue damages were calculated from the combination with wind and wave fatigue damages according to the DNV rule.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.718-719
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• 2015

As a recent global trend, the majority of plant projects are delivered through EPC or EPC-turnkey contracts, where a contractor's liability is more complicated because of the mega size scale and financing method. Previous researches have been lacking a practical usability for project members for liabilities of contracts. Those were focused on solving the claims or schedule calculation issues only. The objective of the present study was to develop a validation process for LDs (liquidated damages) in contractor's liabilities with various case studies and expert judgments. As summarized in this paper, the processes and tools were developed with project life cycle process. The project preparation phase includes 3 step check lists to determine the Go or No-go for projects. In progress phase, contractors should focus on the response strategies for claims with liabilities. The study concludes that those developed processes and tools will help to manage risk of LDs for the contractors in the overseas projects.

• The Korean Society of Law and Medicine
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• v.12 no.2
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• pp.219-263
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• 2011

"Wrongful conception" is a medical malpractice claim in which the plaintiff is the parent of a normal, healthy infant whose conception was unplanned and unwanted. Medical malpractice in wrongful conception can be the result of a failure to provide informed consent to a patient, failure to properly perform a surgery, or a physician's negligent handling of a patient's problems. In the concrete, wrongful conception cases fall into two categories; those involving pre-conception negligence, such as a failed contraceptive, sterilization or failing of the controlling of embryo-number on the IVF, and those involving post-conception negligence, such as a failure to diagnose a pregnancy or to perform an abortion procedure. In addition, Medical malpractice can be the result of a failure to provide informed consent to a patient. When bad results occur by medical malpractice or failure to provide informed consent to a patient, the range of recovery of damages is decided by a traditional civil liability law. However the calculation of damages for wrongful conception is not easy because the high value of life is included in that case. So many courts opinions in foreign country and Seoul High Court decision in 1996 allow damages for the pregnancy, birthing process and sterilization costs, but refuses to allow damages for child rearing expenses. As to the range of recovery of damages for wrongful conception, one approach says that to allow damages in a suit such as this would mean that the physician would have to pay for the fun, joy and affection which plaintiff will have in the rearing and educating of the plaintiff's baby. To allow such damages would be against the dignity of the baby based on article 10 of the Constitution. However another approach says that damages are recoverable for all expenses related to child birth as well as for child rearing costs. Because the damages that the parents should bear a burden to the tort damage done is not a baby itself but child rearing costs. In other words, although the baby is healthy or not, economic burden of the parents can not be disregard. And denial of compensation for costs of child rearing may invalidate the role of liability law, grant the physician with a exemption certificate of liability. As a result, the medical field of procreation can be easily isolated from a liability of reparation. Therefore, on the liability law like the other medical malpractice action, parents who became pregnant or gave a birth by physician, wrongfully performed sterilization operation, etc. should be compensated for all damages relevant to unplanned and unwanted conception or birth as well as costs of child rearing.

• Korean Journal of Construction Engineering and Management
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• v.24 no.1
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• pp.12-20
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• 2023

To calculate the amount of owner-caused and contractor-caused delays based on a simplified delay analysis, which has been customarily used in Korea, has a limitation in reflecting the impact of the concurrent delay and the acceleration work. It also resulted in the apportionment of liquidated damages by applying the ratio of the number of delays between the owner and the contractor. This study analyzes that the conventional method does not meet the international standards. In order to improve the problem of construction delay analysis and the apportionment of liquidated damages based on it, owner delays, contractor delays, concurrent delays, and the impact of acceleration should be analyzed together. This study suggests that in the apportionment of liquidated damages, the extension of time should be extended by the sum of concurrent delays and the owner-caused delays, and liquidated damages should be imposed on delays incurred after the extension of time. It can be seen that it conforms to the international standards. The results of this study are expected to contribute to improving the problems of delay analysis and liquidated damages calculation, which have been conventionally accepted.

• Smart Structures and Systems
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• v.21 no.5
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• pp.677-686
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• 2018

The structural responses are often used to identify the structural local damages. However, it is usually difficult to gain the responses of the track, as the sensors cannot be installed on the track directly. The vehicles running on a track excite track vibration and can also serve as response receivers because the vehicle dynamic response contains the vibration information of the track. A damage identification method using the vehicle responses and sensitivity analysis is proposed for the vehicle-track coupling system in this paper. Different from most damage identification methods of vehicle-track coupling system, which require the structural responses, only the vehicle responses are required in the proposed method. The local damages are identified by a sensitivity-based model updating process. In the vehicle-track coupling system, the track is modeled as a discrete point supported Euler-Bernoulli beam, and two vehicle models are proposed to investigate the accuracy and efficiency of damage identification. The measured track irregularity is considered in the calculation of vehicle dynamic responses. The measurement noises are also considered to study their effects to the damage identification results. The identified results demonstrate that the proposed method is capable to identify the local damages of the track accurately in different noise levels with only the vehicle responses.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1444-1446
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• 1999

In the calculation of lightning-induced voltage, it is used the various parameters obtained by LPATS being operated in KEPCO from 1995. Based on the lightning-induced voltage and the exact lightning position acquired by the developed program, we can predict the extent of damages in distribution systems. The result in this paper is very useful in finding fault location by lightning and performing rapid outage recovery and maintenance of distribution line equipments.

• Journal of Power System Engineering
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• v.13 no.6
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• pp.35-42
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• 2009

The piping systems in the steam-driven power engines lie under the cyclic condition of thermal expansion and contraction by superheated steam. These phenomena might cause some severe damages on the pipes and the accessory devices. To avoid these damages, the calculation of the proper strength and the consideration of the reduced resultant forces on the materials are needed. In the present study, numerical investigations on the effects of the thermal deformation of the industrial piping system were performed with comparison of the design data. Commercial software, ABAQUS with the thermal-fluidic loadings based on the design conditions was used for the thermal stress analysis of the piping system. From the analysis of the initially-designed pipe supporters, the rearrangement was suggested to improve the piping design.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.04a
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• pp.171-174
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• 2000

In this paper, impact sound realization of composite structures is performed to investigate the possibility of a new NDE system - Tapping Sound Analysis (TSA). TSA detects the existence of damages inside the structures by comparing tapping sound with pre-computed sound data of healthy structures. Tapping on the structures is modeled as impact problem and solved using finite element method. Calculation of sound is formulated based on the coupled finite element and boundary element method. Numerical simulation of impact sound and feature extraction scheme show that the impact sound can be used in the identification of damages of laminated composites.