• The Korean Journal of Air & Space Law and Policy
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• v.29 no.1
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• pp.33-66
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• 2014

While the numbers of overseas travelers has been increased rapidly each year, the numbers of passengers in the aircraft also has continued to be increased gradually. In the mist of these increasing numbers, such accidents as threatening an aircraft safety like riot, aircraft hijacking and terrorism have happened constantly. In these circumstances, South Korean government has prescribed "Aviation on Security Act" in accordance with the Convention on International Civil Aviation and other international agreements. This act aims to prevent illegal activities and illegal items on the aircraft to ensure the safety and security of civil aviation. However, this act is not sufficiently regulating all the illegal crimes and illegal items on the flight. For the worse, there is a lack of effective supervisory capacity. Likewise, the inherent problems of the current laws relating to the prevention of the illegal items on the aircraft are appearing on the surface continually. Above all, illegal items on the aircraft are directly connected to the issue of aviation safety and security as well as a safe utilization of the flight service. Thus, when there occurs a serious accident on board, it surely would be led to a huge economic loss not mentioning the loss of lives following the accident. Therefore safety of the flight passengers cannot be guaranteed without ensuring the safety of aircraft facilities and good supervisory mechanism of illegal items on the aircraft. Accordingly, establishing a safe operation order tends to influence economy and tourism of a country in no small measure. Therefore, it is an urgent issue to settle down a reasonable and adequate supervisory regulations regarding the prevention of the illegal items on the aircraft. Consequently, in this article, I studied on a reasonal and effective mechanism to control the prevention of the illegal items and illegal acts on the aircraft in order to ensure a safety and security of civil aircraft.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.555-567
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• 2023

The cracks in the tunnel are currently determined through visual inspections conducted by inspectors based on images acquired using tunnel imaging acquisition systems. This labor-intensive approach, relying on inspectors, has inherent limitations as it is subject to their subjective judgments. Recently research efforts have actively explored the use of deep learning to automatically detect tunnel cracks. However, most studies utilize public datasets or lack sufficient objectivity in the analysis process, making it challenging to apply them effectively in practical operations. In this study, we selected test datasets consisting of images in the same format as those obtained from the actual inspection system to perform an objective evaluation of deep learning models. Additionally, we introduced ensemble techniques to complement the strengths and weaknesses of the deep learning models, thereby improving the accuracy of crack detection. As a result, we achieved high recall rates of 80%, 88%, and 89% for cracks with sizes of 0.2 mm, 0.3 mm, and 0.5 mm, respectively, in the test images. In addition, the crack detection result of deep learning included numerous cracks that the inspector could not find. if cracks are detected with sufficient accuracy in a more objective evaluation by selecting images from other tunnels that were not used in this study, it is judged that deep learning will be able to be introduced to facility safety inspection.

• Journal of the Korean Geosynthetics Society
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• v.9 no.4
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• pp.17-25
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• 2010

Evaluation of stability in traditional designing of reinforced soil structures is executed by examination of internal and external stability. Analysis of internal stability is for pull-out and ductile strength. Analysis of external stability is for settlement, overturning and sliding. To minimize inherent uncertainties of soil properties and analytical model, reliability analysis was developed recently. In this study, reliability analysis method considering simultaneous failure probability for various failure mode of internal and external stability is proposed. By applying uni-modal bounds, Stability of system reliability of reinforced soil structures is evaluated by integrating multi failure mode for various analytical model. Because of complex consideration for various failure shapes and modes, it is possible to secure advanced safety by using simultaneous failure probability. And evaluation of reinforced soil structure is executed by representative index, simultaneous failure probability, than previous method.

• The Journal of Society for e-Business Studies
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• v.21 no.1
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• pp.1-14
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• 2016

This research proposes a method that aims to evaluate the risk levels of websites based on exposure risks of privacy information. The proposed method considers two aspects as follows. First, we define the risk levels of each privacy information according to its own inherent risk. Second, we calculate the visiting probability of a webpage to measure the expected of the actual exposure of privacy information on that webpage. In this research, we implemented an system to prove that automatically collects websites and calculates their risk levels. For the experiments, we used a real world dataset consisting of a total of websites for 4 categories such as university, bank, central government agency, and education. The experiment results show that the websites in the bank category are relatively well managed, while the others are needed to cope with the exposure of privacy information. Finally, the proposed method in this research is expected to be further utilized in establishing a priority-based approach to alleviate of the privacy information exposure problems.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.5 s.39
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• pp.91-99
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• 2004

In general, stadium structure with long span has low inherent natural frequency. In the stadium structure, structural behavior similar to resonance can be occurred easily by spectator rhythmical movements of which exciting period is small comparatively. It is required to investigate the safety and the serviceability of stadium structure. Therefore, there exists a necessity for accurate vibration analysis. Accurate analysis of stadium structure subjected to dynamic load is required for economical construction and safe design of stadium structure. Stadium structure should be modeled by refined mesh for accurate vibration analysis. As the mesh of stadium structure is refined, the number of divided elements increases in numerical analysis. The number of node is increased and numerous computer memories or computational time are required. So it is very difficult to analyze refine model of stadium structures by using the commercial programs. It is possible to efficient vibration analysis of stadium structure by finite element modeling method using equivalent beam element proposed in this paper, because the number of nodes is decreased remarkably.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1577-1584
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• 2002

This paper develops a finite element model for studying the occupant behavior and injury cofficients of a large-sized cab-over type truck. Since it does not have a room to absorb collision energy and deformation in front of the passenger compartment the deformation is directly transmitted to the passenger compartment. Moreover, since its steering column is attached on the frame, severe deformation of the frame directly affects on the steering wheel's movement. Therefore, if the occupant behavior and injury coefficients analysis is performed using a finite element model developed based on a sled test, it is very difficult to expect acquiring satisfactory results. Thus, the finite element model developing in this paper is based on the frontal crash test in order to overcome the inherent problems of the sled test based model commonly used in the passenger car. The occupant behavior and injury coefficients analysis is performed using PAM-CRASH installed in super-computer SP2. In order to validate the reliability of the developed finite element model, a frontal crash test is carried out according to a test method used fur developing truck occupant's secondary safety system in european community and japan. That is, test vehicle's collision direction is vertical to the rigid barrier and collision velocity is 45kph. Thus, measured vehicle pulses at the lower parts of the left and right B-pilla., dummy chest and head deceleration profiles, HIC(head injury criterial) and CA(chest acceleration) values, and dummy behavior from the frontal crash test are compared to the analysis results to validate reliability of the developed model.

• Journal of Society of Preventive Korean Medicine
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• v.16 no.1
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• pp.1-13
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• 2012

The objective of this study is to discuss the role of integrative medicine (IM) in contemporary health care settings, and how and which factors affect and facilitate the success of IM in terms of the integration of complementary and alternative medicine (CAM) and conventional medicine in primary health care (PHC). IM is meant to provide the best possible health care, for both patient and physician. The way of IM use in the developed countries presents various ways that IM can be provided, and it appears that strategies have been successfully developed to facilitate integration. Although few of the barriers to the integration of CAM and conventional medicine have been resolved, concerns over the legitimacy of CAM in health care (e.g., safety, biomedical evidence, and efficacy) are being overcome by the use of evidence-based practice in IM delivery. There are dominant models of IM that have been developed. The model types signify different levels of equity between CAM and conventional medicine in regard to the power, autonomy, and control held by each. However, the factors common to all IM models, whether describing CAM as supplementary or complementary to conventional medicine, is the concept of a health care model that aspires to be client-centred and holistic, with focus on health rather than disease as well as mutual respect among peer practitioners. Finally, this study concluded that the growth and viability of traditional Korean medicine(TKM) depend on evidence-based practices and identifying the successful influences on the integration of TKM and conventional medicine for recognition of its inherent value in PHC. Some recommendations for the integration of TKM and conventional medicine were suggested.

• Journal of Mechanical Science and Technology
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• v.19 no.3
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• pp.778-791
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• 2005

A novel pneumatic artificial muscle actuator (PAM actuator), which has achieved increased popularity to provide the advantages such as high strength and high power/weight ratio, low cost, compactness, ease of maintenance, cleanliness, readily available and cheap power source, inherent safety and mobility assistance to humans performing tasks, has been regarded during the recent decades as an interesting alternative to hydraulic and electric actuators. However, some limitations still exist, such as the air compressibility and the lack of damping ability of the actuator bring the dynamic delay of the pressure response and cause the oscillatory motion. Then it is not easy to realize the performance of transient response of pneumatic artificial muscle manipulator (PAM manipulator) due to the changes in the external inertia load with high speed. In order to realize satisfactory control performance, a variable damper-Magneto­Rheological Brake (MRB), is equipped to the joint of the manipulator. Superb mixture of conventional PID controller and a phase plane switching control method brings us a novel controller. This proposed controller is appropriate for a kind of plants with nonlinearity, uncertainties and disturbances. The experiments were carried out in practical PAM manipulator and the effectiveness of the proposed control algorithm was demonstrated through experiments, which had proved that the stability of the manipulator can be improved greatly in a high gain control by using MRB with phase plane switching control method and without regard for the changes of external inertia loads.

• Ocean Systems Engineering
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• v.6 no.2
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• pp.143-159
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• 2016

Cargo, such as a Tension Leg Platform (TLP), Semi-submersible platform (Semi), Spar or a circular Floating Production Storage and Offloading (FPSO), are frequently dry-transported on a Heavy Lift Vessel (HLV) from the point of construction to the point of installation. The voyage can span months and the overhanging portions of the hull can be subject to frequent wave slamming events in rough weather. Tie-downs or sea-fastening are usually provided to ensure the safety of the cargo during the voyage and to keep the extreme responses of the cargo, primarily for the installed equipment and facilities, within the design limits. The proper design of the tie-down is dependent on the accurate prediction of the wave slamming loads the cargo will experience during the voyage. This is a difficult task and model testing is a widely accepted and adopted method to obtain reliable sea-fastening loads and extreme accelerations. However, it is crucial to realize the difference in the inherent stiffness of the instrument that is used to measure the tri-axial sea fastening loads and the prototype design of the tie-downs. It is practically not possible to scale the tri-axial load measuring instrument stiffness to reflect the real tie-down stiffness during tests. A correlation method is required to systematically and consistently account for the stiffness differences and correct the measured results. Direct application of the measured load tends to be conservative and lead to over-design that can reflect on the overall cost and schedule of the project. The objective here is to employ the established correlation method to provide proper high-frequency responses to topsides and hull design teams. In addition, guidance for optimizing tie-down design to avoid damage to the installed equipment, facilities and structural members can be provided.

• Proceedings of KOSOMES biannual meeting
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• 2003.11a
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• pp.45-51
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• 2003

The ship's signal sound dispersed by air, obstacles, and noises due to absorption, reflection, and disturbances, respectively. It is one of the factors of marine casualties by misjudgment if receiving direction The last target of this study is to prevent inherent marine casualty using the analysis-evaluation techniques if the interferences of ship's signal sound. In this work, three-dimensional sound field control model is proposed to simulate various sound transmitting characteristics according to sea environments at sea The efficiency test of the model was carried out using VR-based ship simulator.