• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2004.11a
• /
• pp.154-159
• /
• 2004

A new finite difference scheme is studied fur the simulation of free surface, surface the third derivative tenn for the wave elevation is artificially added in the the free-surface boundary condition. This study presents a comparative analysis with simulations performed by using the classical MAC method. More systematic computations are carried out by changing the submergence depth and angle of attack. Through the numerical simulation, it is found that a new numerical method becomes more efficient for the reason that the free surface elevation is reasonably developed at tire rear of trailing edge.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2004.11a
• /
• pp.228-233
• /
• 2004

The characteristics of the probability distribution for mechanical properties, e.g. tensile strength, reduction of area ana elongation, for STS304 stainless steel in elevated temperature were investigated from tensile test performed by constant cross head speea controls with 1mm/min, Recently, in order to clarify the strengthening mechanisms at high temperature, a new scheme to improve high temperature mechanical properties is desired. Therefore, the test ,technique development of high temperature creep behaviors for this material is very important. In this paper, the creep praperties and creep life prediction by Larson-Miller parameter method for STS304 stainless steel to be used for other high temperature components were presented at the elevated temperatures of 600, 650 and $700^{\circ}C$.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2001.10a
• /
• pp.132-137
• /
• 2001

This paper presents a method of seismic analysis for a 2-D fluid-structure-soil interaction systems. With this method, the fluid can be modeled by spurious free 4-node displacement-based fluid elements which use rotational penalty and mass projection technique in conjunction with the one point reduced integration scheme to remove the spurious zero energy modes. The structure and the near-field soil are discretized by the standard 2-D finite elements, while the unbounded far-field soil is represented by the dynamic infinite elements in the frequency domain. Since this method directly models the fluid-structure-soil interaction systems, it can be applied to the dynamic analysis of a 2-D liquid storage structure with complex geometry. Finally, results of seismic analyses are presented for a spent fuel storage tank embedded in a layered half-space and a massive concrete dam on a layered half-space.

• Safety and Health at Work
• /
• v.2 no.3
• /
• pp.229-235
• /
• 2011

Objectives: In this study, we summarized the External Quality Assessment Scheme (EQAS) for the biological monitoring of occupational exposure to toxic chemicals which started in 1995 and continued until a $31^{st}$ round robin in the spring of 2010. The program was performed twice per year until 2009, and this was changed to once a year since 2010. The objective of the program is to ensure the reliability of the data related to biological monitoring from analytical laboratories. Methods: One hundred and eighteen laboratories participated in the $31^{st}$ round robin. The program offers 5 items for inorganic analysis: lead in blood, cadmium in blood, manganese in blood, cadmium in urine, and mercury in urine. It also offers 10 items for organic analysis, including hippuric acid, methylhippuric acid, mandelic acid, phenylglyoxylic acid, N-methylformamide, N-methylacetamide, trichloroacetic acid, total trichloro-compounds, trans,trans-muconic acid, and 2,5-hexanedione in urine. Target values were determined by statistical analysis using consensus values. All the data, such as chromatograms and calibration curves, were reviewed by the committee. Results: The proficiency rate was below 70% prior to the first round robin and improved to over 90% for common items, such as PbB and HA, while those for other items still remained in the range of 60-90% and need to be improved up to 90%. Conclusion: The EQAS has taken a primary role in improving the reliability of analytical data. A total quality assurance scheme is suggested, including the validation of technical documentation for the whole analytical procedure.

• Journal of Satellite, Information and Communications
• /
• v.10 no.4
• /
• pp.146-150
• /
• 2015

The COSPAS-SARSAT committee decides MEOSAR (Medium-Earth Orbit for search and rescue) service development for installing 406MHz SAR instruments on their respective MEO navigation satellite system of the United States, EU, and Russia, since 2000. The transmitted beacon signal is separately arrived by satellites with different FOA (Frequency of Arrival) and TOA (Time of Arrival). It is directly transferred to MEOLUT. In MEOLUT, a LUT track at least 3 or 4 satellites simultaneously and estimate location of beacon using time difference of arrival (TDOA) and frequency difference arrival (FDOA). But the transmitted distress signals may be overlapped each other because the distress beacons transmit signal on mean interval of 50 seconds in arbitrary time. It's difficult that simultaneously estimate location of beacon by current scheme for several overlapped distress signal. So we use cross ambiguity function (CAF) Map algorithm and present Multi-CAF MAP scheme in order to satisfy performance requirement of system. The performance is analyzed for COSAPS-SARSAT MEOSAR.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2000.04a
• /
• pp.18-22
• /
• 2000

This paper is transient motions of a very large floating structure subjected to dynamic load induced by wave. A time domain method is applied to the hydroelasticity problems for this purpose. The method is based on source-dipole and FEM scheme and on Newmark $\beta$ method to pursuit time step process taking advantage of the memory effect. The present method is appied to hydroelastic response analysis in regular waves and impact responses due to dropping aircraft.

• Journal of Broadcast Engineering
• /
• v.10 no.1 s.26
• /
• pp.14-21
• /
• 2005

This paper described an Enhanced-xVSB system for improving mobile/pedestrian reception performance to the ATSC(Advanced Television System Committee) DTV 8-VSB transmission standard. E-xVSB system can transmit a mixture of normal (8-VSB) stream and enhanced (robust) stream. The robust stream has a higher threshold of visibility (TOV) compared to the standard stream, and legacy receivers ignore the robust packets. Thus, Enhanced-xVSB system is fully backward compatible with a current ATSC standard. For mobile and portable reception support, E-xVSB system adopts a reduced constellation methodas well as enhanced trellis-coded modulation scheme. E-xVSB system supports a variety of enhanced modulation schemes : Pseudo-2VSB, Enhanced-4VSB, modified Enhanced-8VSB and Hybrid-VSB. Proposed E-xVSB system performs well under serious dynamic multipath reception environment.

• Journal of Broadcast Engineering
• /
• v.24 no.2
• /
• pp.329-340
• /
• 2019

Recently, broadcasting technologies have evolved as high-quality AV services such as domestic terrestrial UHD(Ultra-High Definition) broadcasting have been increasing, and broadcasting standards have been newly defined. Also, as network technology develops, contents are consumed not only in the country but also the world. Accordingly, content insertion technology, which is a method of providing suitable contents in accordance with the national and local environments, will be needed. This paper proposes a content insertion service system model and synchronization scheme using ATSC(Advanced Television Systems Committee) 3.0 Event Signaling standard under heterogeneous network environment of broadcasting network and internet network based on transmission standard DASH(Dynamic Adaptive Streaming over HTTP)/ROUTE(Real time Object delivery Over Unidirectional Transport) and MMT(MPEG Media Transport) of terrestrial UHD broadcasting. It also verifies that the service operates in an environment that meets the broadcast standard.

• Journal of Arbitration Studies
• /
• v.25 no.4
• /
• pp.119-136
• /
• 2015

The contracting parties must be provided a litigation scheme in order to resolve a dispute. This means taking advantage of effective measures for mediation or arbitration. A lease transaction is likely to occur mainly after a dispute. It is necessary to take the appropriate measures in advance. In general, when a variety of contracts are created, conflicts arise and disputes have to be resolved through mediation and arbitration documents, and adjustment or intervention is called for. Arbitration system is a system that is established based on the trust of the arbitral tribunal. For such system, quality education for enhancing professionalism required of the arbitrator is important. A party responding to an arbitration agreement presents a problem. The current system must ensure that there are no disadvantaged parties. However, a party must depend on an arbitration agreement that is part of the law rescue system. A litigation support by the local Bar Association must be carried out. It should be notified of the contents of the contract to select a strategy that will best resolve the conflict. In the case of lease transactions, there is a need to create a scheme to make a standard agreement that inserts an arbitration clause. Lease sale and purchase agreement or lease agreement is a form of contract that has been frequently used. Here, the arbitration agreement clause for a lawyer that will serve as arbitrator should be inserted. It is a scheme that can be activated for individuals in poor areas. In addition, it is possible to see it taking a scheme to take advantage of the lawyer system for the future of the town. The Attorney System of a town is a system that the Korean Bar Association, Legal Department has put in place since 2013. If a real estate trade dispute occurs, the role of the intermediary attorney should be to carry out his duties efficiently. In the case of real estate transaction conflicts, the lawyer of the village should be registered as the arbitrator. It is important to establish a basis of regulations through this type of real estate transaction accident analysis. Before proceeding with various adjustment systems, it is desirable to expand the arbitration region. Now we need a realtor amendment. It is the part where fragmentation of intermediary qualification is required, along with the eligibility of a subdivision.

• The Korean Journal of Air & Space Law and Policy
• /
• v.12
• /
• pp.36-65
• /
• 2000

The Montreal Convention markedly changed the rules governing the international carriage by air of passenger, baggage and cargo. The introduction of a considerable number of modernized major elements including electric ticketing system, the unlimited passenger liability regime and a supplementary (fifth) jurisdiction should help to remove aged scheme that now exists in the Warsaw Convention and other related instruments. The key issue of the electric ticketing system recognized by the Convention IS how to describe reasonably and adequately the terms of written notices, in the light of the principle of consumer protection. Regarding liability regime for passengers, an unlimited passenger liability regime is realized. The carrier, in the first tier, is subject to a strict liability regime of up to 100,000 SDRs, and in the second tire, a regime of presumed fault liability without numerical liability limits. To add to the present four fora, the fifth forum is permitted. Regarding damage resulting the death or injury of a passenger, an action for damages may also be brought in its home territory with the considerably qualified narrow requirements. A strange deviation from the well-established "Procedure for Approval of Draft Convention" carried out by the Legal Committee left a considerable number of unrefined and incomplete passages. In the near future, their modification should be required.