• Journal of the Korean Society for Nondestructive Testing
• /
• v.31 no.5
• /
• pp.479-486
• /
• 2011

In image-based CFD modeling of carotid bifurcation hemodynamics, it is often not possible (or at least not convenient) to impose measured velocity profiles at the common carotid artery inlet. Instead, fully-developed velocity profiles are usually imposed based on measured flow rates. However, some studies reported a pronounced influence of inflow boundary conditions that were based on actual velocity profiles measured by magnetic resonance imaging which showing the unusual presence of a high velocity band in the middle of the vessel during early diastole inconsistent with a Dean-type velocity profile. We demonstrated that those velocity profiles were induced by the presence of modest secondary curvature of the inlet and set about to test whether such more "realistic" velocity profiles might indeed have a more pronounced influence on the carotid bifurcation hemodynamics. We found that inlet boundary condition with axisymmetric fully-developed velocity profile(Womersley flow) is reasonable as long as sufficient CCA inlet length of realistic geometry is applied.

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

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.17 no.1
• /
• pp.47-52
• /
• 2011

On the high seas, under international law, a ship is subject to the jurisdiction of the state whose flag she flies. Vessels of any flag are free to navigate the high seas without interference from other states. Thus, there are certain limits of coastal state's exercising law enforcement jurisdiction over a foreign flag vessel on the high seas. However, there are exceptions to exclusive flag state jurisdiction. One of them is the theory of constructive presence. The other is theory of partial execution. Korea Coast Guard's law enforcement authority should be exercised more actively based on those theories supported by the international cases.

• Journal of Haehwa Medicine
• /
• v.22 no.1
• /
• pp.1-10
• /
• 2013

Through a consideration of the contralateral collateral needling(繆刺) from "Neijing", the conclusions are as follows. The contralateral collateral needing is defined as a disordered state, and also as the pricking bloodletting method. Unlike the seasonal deficiency pathogen(虛邪), which are affected by the four seasons, the subject of the contralateral collateral needling is the extra pathogen(奇邪), which is the cause of the extra disease(奇病), therefore the treatment should be different from the general. The contralateral collateral needling is generally used when a pain is generated from the veins(絡) by an external pathogen(邪). However, it can be used as the treatment for an emotional disorder, such as flight or sorrow, or a body constituent(身形) disorder caused by internal parts of the five viscera. Although the contralateral collateral needling(繆刺) and the contralateral meridian needling(巨刺) share the left and right cross treatment(右取左, 左取右) in common, but they are different in every aspect, as the causes, transmutation, location, and feature of disease, relation of qi and blood, and location and method of needling(刺鍼). The medical procedure of the contralateral collateral needling is collateral needling(刺絡) the parts of blood collaterals(血絡) or bruising(痏) well points(井穴) of the end of the both sides of limbs, and using the left and right cross treatment when the former methods are not making any progress. The symptoms of contralateral collateral needling are head, chest, and abdomen pains, and they are treated at the end of the limbs. The bloodletting method(刺絡法), extracting a little amount of blood at well points or blood collaterals, or the collateral vessel pricking therapy(瀉血法), extracting a lot of blood by using cupping(附缸), for example, are contemporary successions of the collateral needling(絡刺), the leopard-spot needling(豹文刺), and the contralateral collateral needling.

• Journal of Navigation and Port Research
• /
• v.38 no.2
• /
• pp.141-146
• /
• 2014

NIR(New Inspection Regime, hereinafter NIR) relating to the PSC(Port State Contorl, hereinafter PSC) has implemented in Asia-Pacific region under Tokyo-MOU from last January 2014. The most noticable difference between NIR and existing TF(Target Factor, hereinafter TF) is to evaluate company performance and to conduct PSC with flexible inspection interval on the basis of Ship Risk Profile; High Risk Ship, Standard Risk Ship and Low Risk Ship. Particularly deficiencies related to ISM Code, more than 5 deficiencies and detention record have a serious effect on the evaluation of Ship Risk Profile. Therefore ship and company are requested to ensure proper implementation of Safety Management System for the changed PSC tendency. Also RO(Recognized Organization, hereinafter RO) and Administration respectively should take suitable actions different to previous measures, such as implementation of cooperation and support system between vessel and company, changing subject and object for avoiding Mannerism in SMS audit, strengthening supervision on RO by Administration and establishment of private-public Partnership network.

• Journal of the Society of Naval Architects of Korea
• /
• v.47 no.1
• /
• pp.99-111
• /
• 2010

Recently, a very large vessel's maneuvering performance, rudder performance and rudder design's importance is considered to be an important subject. There have been few studies on the design process of rudder device before. The aim of this paper is to investigate a design process of rudder device and to propose a generalized design process of rudder device. Firstly, we investigated the rudder device design process of Korean major shipyards. And the differences of a torque calculation method, rudder section design, maneuvering performance examination method, etc were analyzed theoretically. Secondly, the design process of rudder device was divided into concept design, initial design and detail design. In concept design, a rudder area was estimated and its validity was examined. In initial design, rudder profile and design method has been selected through rudder form determination process. And principal dimension and steering gear capacity were determined. Maneuvering performance was also examined by simulation tool. In detail design, design criteria considered in rudder initial design has been investigated thoroughly. Also a rudder torque, rudder cavitation performance and rudder structure analysis were estimated. And maneuvering performance was also examined by model test. Finally, based on the results of investigation, the design process of rudder device was generalized and proposed.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.13
• /
• pp.411-437
• /
• 2000

It is unsafe to attempt a complete definition of the expression 'perils of the seas', because in practice the question 'what is a peril of the seas' is inextricably woven up with the further question, 'was the loss proximately caused by the sea peril ?' Such casualties as stranding, collision and heavy weather appear with monotonous regularity in the daily reports, and are the obvious examples. However, what can be included in the term 'perils of the seas' seems to be inexhaustible, although most circumstances appear to have been covered by the Courts. Two cases heard in 1887 were instrumental in defining perils of the seas. In The Xantho Lord Herschell made the following remarks: "The term ... does not cover every accidents or casualty which may happen to the subject matter of insurance on the sea. It must be a peril 'of' the sea. Not every loss or damage of which the sea is the immediate cause is covered by these words. They do not protect, for example, against that natural and inevitable action of the winds and waves which results in what may be described as wear and tear. There must be some casualty, something which could not be foreseen as one of the necessary incidents of the adventure. The purpose of the policy is to secure an indemnity against accidents which may happen, not against events which must happen. ... If a vessel strikes upon a sunken rock in fair weather and sinks, this is a loss by perils of the sea."

• Journal of Navigation and Port Research
• /
• v.33 no.6
• /
• pp.423-428
• /
• 2009

Recently, the marine traffics have been increased along with enlargement of overseas commerce. Increasing the marine traffic may make higher the risk of marine accidents. Especially, the rate of accidents on costal area are more frequently. As if the marine safety information can be afforded to vessel and shore, the accident rate would be down. AIS AtoN is the navigational safety support device which is subject to functional requirements of IALA and technical standards of ITU. In this paper, we extend and implement the user-defined specification of AIS AtoN with message 21 for AIS basic information, messsage 6 for status report and message 12/14 for safety management.

• Nuclear Engineering and Technology
• /
• v.47 no.3
• /
• pp.340-350
• /
• 2015

This paper proposes strain-based acceptance criteria for assessing plastic instability of the safety class 1 nuclear components made of ferritic steel during level D service loads. The strain-based criteria were proposed with two approaches: (1) a section average approach and (2) a critical location approach. Both approaches were based on the damage initiation point corresponding to the maximum load-carrying capability point instead of the fracture point via tensile tests and finite element analysis (FEA) for the notched specimen under uni-axial tensile loading. The two proposed criteria were reviewed from the viewpoint of design practice and philosophy to select a more appropriate criterion. As a result of the review, it was found that the section average approach is more appropriate than the critical location approach from the viewpoint of design practice and philosophy. Finally, the criterion based on the section average approach was applied to a simplified reactor pressure vessel (RPV) outlet nozzle subject to SSE loads. The application shows that the strain-based acceptance criteria can consider cumulative damages caused by the sequential loads unlike the stress-based acceptance criteria and can reduce the overconservatism of the stress-based acceptance criteria, which often occurs for level D service loads.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.20 no.2
• /
• pp.179-185
• /
• 2014

A use of Asbestos onboard was banned by the provisions of SOLAS since 1 January 2011. And this provision was also implemented by the Rule for Ship's Facilities in Korea. However, these provisions were only declaration and there were no detailed measures for detect, removal and confirmation. In this study, by reviewing the Ship Recycling Convention, IMO circulars and Asbestos Safe Management Act, the following strategies for each concerned parties were proposed. The administration and class society should establish the provisions for appointment of subject vessel which to be inspected for asbestos, criteria for asbestos management and appointment of handling expert. The shipbuilder and equipment manufacturer should make written confirmation that asbestos was not used in their product. And shipowner and ship manager should establish procedure for onboard control of asbestos in the ship's safe management system.