• Geomechanics and Engineering
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• v.36 no.6
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• pp.545-561
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• 2024

Piled raft foundation has become widely used in the recent years because it can increase bearing capacity of foundation with control settlement. The design for a piled raft in terms vertical load and lateral load need to understands contribution load behavior to raft and pile in piled raft foundation system. The load-bearing behavior of the piled raft, especially concerning lateral loads, is highly complex and challenge to analyze. The complex mechanism of piled rafts can be clarified by using three dimensional (3-D) Finite Element Method (FEM). Therefore, this paper focuses on free-standing head pile group, on-ground piled raft, and embedded raft for the piled raft foundation systems. The lateral resistant of piled raft foundation was investigated in terms of relationship between vertical load, lateral load and displacement, as well as the lateral load sharing of the raft. The results show that both vertical load and raft position significantly impact the lateral load capacity of the piled raft, especially when the vertical load increases and the raft embeds into the soil. On the same condition of vertical settlement and lateral displacement, piled raft experiences a substantial demonstrates a higher capacity for lateral load sharing compared to the on-ground raft. Ultimately, regarding design considerations, the piled raft can reliably support lateral loads while exhibiting behavior within the elastic range, in which it is safe to use.

• Tribology and Lubricants
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• v.35 no.1
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• pp.44-51
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• 2019

The paper presents the rotordynamic performance measurements and model predictions of a fuel cell electric vehicle (FCEV) air compressor supported on gas foil bearings (GFBs). The rotor has an impeller on one end and a thrust runner on the other end. The front (impeller side) and rear (thrust side) gas foil journal bearings (GFJBs) are located between the impeller and thrust runner to support the radial loads, and a pair of gas foil thrust bearings are located on both sides of the thrust runner to support the axial loads. The test GFJBs have a partial arc shim foil installed between the top foil and bump strip layers to enhance hydrodynamic pressure generation. During the rotordynamic performance tests, two sets of orthogonally installed eddy-current displacement sensors measure the rotor radial motions at the rotor impeller and thrust ends. A series of speed-up and coast-down tests to 100k rpm demonstrates the dominant synchronous (1X) rotor responses to imbalance masses without noticeable subsynchronous motions, which indicates a rotordynamically stable rotor-GFB system. Finite element analysis of the rotor determines the rotor free-free (bending) natural modes and frequencies well beyond the maximum rotating frequency. The predicted damped natural frequencies and damping ratios of the rotor-GFB system reveal rotordynamic stability over the speeds of interest. The imbalance response predictions show that the predicted critical speeds and rotor amplitudes strongly agree with the test measurements, thus validating the developed rotordynamic model.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.4
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• pp.34-45
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• 2004

Existing Semangeum's water balance analysis simplifies whole basin to single basin and achieved volume of effluence that produce by Kajiyama way to foundation. But Semangeum is complicated and various rice-wine strainer supply system. And there is difficulty to apply as elastic when water balance element is changed at free point. Divided to unit possession station for suitable water balance analysis model application to Semangeum in this study. And developed basin water balance model of GIS base that can do details analysis is bite about development and transfer of an appropriation in the budget of basin water resources. Achieved study including abstraction and concept design that use UML (unified modeling language) diagram for details analysis, stream network composition for rice-wine strainer supply system application, preprocessing of GIS base and postprocessing module development, model revision and verification etc. Support of this water balance analysis model is available to establish efficient water resources administration plan through outward flow process analysis of water resources. And support is considered to be possible in more convenient and, reasonable water resources administration way establishment by minimizing manual processing in systematic water resources government official to user and support diversified analysis system.

• Journal of Arbitration Studies
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• v.15 no.2
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• pp.61-91
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• 2005

It is well recognized that the availability of prompt, effective and economical means of dispute resolution is an important element in the orderly growth and encouragement of international trade and investment. Increasingly, ADR(Alternative Dispute Resolution) including arbitration and mediation, instead of litigation in national courts, has become the preferred means of resolving private international commercial disputes. Under the situation, efforts for settlement of trade and investment disputes by ADR have been made between Korea and China through trade and investment agreements and arbitration agreement. Judging from the importance of economic exchange between Korea and Qingdao including Shandong Province, The Korean Commercial Arbitration Board(KCAB) and The Qingdao Arbitration Commission(QAC) should strengthen mutual cooperation to develop efficient methods of resolving commercial disputes arising between the two countries and to assist parties in solving those disputes through conclusion of arbitral agreement. Recently, efforts for conclusion of a Korea-China-Japan Free Trade Agreement(FTA) received strong support at Korea-Japan and Korea-China Summit Meeting held on June and July, 2003 respectively. If the conclusion of FTA among the three countries would be realized, it would promote regional trade and investment, contributing to economic growth in the Northeast Asian region. Under the circumstances, the key arbitral institutions including KCAB and QAC should consider to take the initiative in setting up tentatively called ${\ulcorner}$Joint Arbitration Center for Northeast Asia${\lrcorner}$ for which the CAMCA of NAFTA will be the good example.

• Advances in nano research
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• v.9 no.4
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• pp.263-276
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• 2020

In this article, the acoustic responses of free vibrated natural fibre-reinforced polymer nanocomposite structure have been investigated first time with the help of commercial package (ANSYS) using the multiphysical modelling approach. The sound relevant data of the polymeric structure is obtained by varying weight fractions of the natural nanofibre within the composite. Firstly, the structural frequencies are obtained through a simulation model prepared in ANSYS and solved through the static structural analysis module. Further, the corresponding sound data within a certain range of frequencies are evaluated by modelling the medium through the boundary element steps with adequate coupling between structure and fluid via LMS Virtual Lab. The simulation model validity has been established by comparing the frequency and sound responses with published results. In addition, sets of experimentation are carried out for the eigenvalue and the sound pressure level for different weight fractions of natural fibre and compared with own simulation data. The experimental frequencies are obtained using own impact type vibration analyzer and recorded through LABVIEW support software. Similarly, the noise data due to the harmonically excited vibrating plate are recorded through the available Array microphone (40 PH and serial no: 190569). The numerical results and subsequent experimental comparison are indicating the comprehensiveness of the presently derived simulation model. Finally, the effects of structural design parameters (thickness ratio, aspect ratio and boundary conditions) on the acoustic behaviour of the natural-fibre reinforced nanocomposite are computed using the present multiphysical model and highlighted the inferences.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.4
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• pp.351-359
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• 2004

Aluminum honeycomb sandwich panel (AHSP) not only have high flexural rigidity and strength per density but also excellence in anti-vibration and anti-noise properties. Their properties are very useful for build airplane and high speed crafts, which need lighter-weighted and more strengthed element. Recently, the AHSP is regarded as a promising strength member of light structures like the hull of high speed crafts. Generally, the core shape of aluminum sandwich panel (ASP) is the hexagonal shape of honeycomb. But, in this paper, authors proposed the ASP with pyramid core, as the ASP model of new type, and analysed the structural and vibrational characteristics for aluminum pyramid sandwich panel (APSP) as this new ASP type, according to the thickness variation of core and face, the height variation of core. The applied sandwich models have isotropic and symmetrical aluminum faces and pyramid cores. And, the applied boundary conditions are simple, fixed and free support.

• Journal of the Korean Institute of Gas
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• v.20 no.6
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• pp.58-64
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• 2016

Vibrational characteristics of curved pipe structures are investigated with respect to the change of inside flow velocities. Based upon the Hamilton's principle, the equations of motions are derived, and the finite element equation is constructed to solve the frequency equation for curved pipe structures. When the initial tension is neglected in cured pipes, the natural frequencies are reduced as flow velocity increases, and the rapid decreases of the natural frequencies take place. However, when the initial tension is taken into account, the natural frequencies are not changed with the change of the flow velocity. In free vibrational simulation of pipe systems, it is necessary to calculate the initial force due to the velocity and the pressure of the fluid flow from the equilibrium. The force should be included in the equation of motion of the systems to get more accurate natural frequencies. The mechanical properties like stiffness or the location of pipe support need to be changed to avoid resonance. The natural frequencies are to be isolated from the frequency range of dominant vibration modes. The angles of elbows do not affect the change of the fundamental natural frequency, but affect the change of the third or higher natural frequencies.

• Journal of Navigation and Port Research
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• v.27 no.1
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• pp.9-18
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• 2003

This is a study for international competitiveness analysis if korea ship management service using the collected data from the fields in industry. making a comparison if ship management company between domestic ones in Korea and mutinational ones in international market is more suitable for it's purpose. but competitiveness level of korean ship management companies are too low to compare. Therefore in this study, ship management devision in Korea overseas shipping companies are selected as a target of camparision and the representative of Korea ship management industry. The analysis of competitiveness is divided by price competition and non-price competition. The former is consist of element likes as crew management cost, dry-docking cost, repair cos, stores & spares cost, lubricants cost and management free cost, The later os consist of element like as quality of sea & shore personnel, efficiency of company's organization, ability of management system. qualifications & certifications, know -hoe for the ship management, structure of control & support ship and office automation & IT system. According to this analysis the ship management division in korean shipping companied are superior to the foreign specialized ship management companies generally. So, it is necessary that korea ship management industry attempt level-up continously and expand into international ship management market positively.

• The Journal of the Convergence on Culture Technology
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• v.7 no.3
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• pp.375-382
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• 2021

Adolescents with disabilities have unnatural behavior and language, which makes it difficult to use soft and flexible language and behavior, and lack of learning experience has limitations in not being free in mature behavioral communication. Eurhythmics musical rhythm elements were divided into time and space, power and weight, and balance and fluidity and reflected in teaching and learning so that adolescents with disabilities could have comfortable, creative, and original thoughts that bring about changes in thawing. In order to increase the effectiveness of education in the direction of observing the effect of improving self-esteem, communication, and creativity of adolescents with disabilities, the study guide applying the Eurhythmics rhythm element was fused with music education, art education, and physical education, and interviewed by selecting research participants. Based on the questionnaire, an observation method suitable for the study of adolescents with disabilities was conducted. As a result of the study, it was observed that the educational effect of the disabled youth was improved as a result of conducting the class by applying the Eurhythmics rhythm elements time and space, force and weight, balance and fluidity by integrating music, art, and physical education(line dance, playtime). Therefore, to supplement the limitations in this learning process, various educational methods applicable to the education of youth with disabilities, a support system that can reflect Eurhythmics education through physical play, and a method to properly compose various learning tools do.

• Journal of the Korea Institute of Building Construction
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• v.11 no.3
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• pp.301-309
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• 2011

Apartment housings that adopt a bearing wall structure design, which account for a majority of the housing units available in Korea, are not free from structural constraints that limit the extension of their service life. The resulting need for reconstruction from the ground up requires a massive consumption of resources and energy, and triggers environmental pollution resulting from construction wastes. As a solution to such issues, the government enforces incentive schemes to promote a remodeling-friendly rahmen structure design. Green Frame, which is a novel concept of composite precast concrete structure to support rahmen structure apartment housing buildings, can address the constraints of bearing wall structure and conventional rahmen structure designs that limit the potential for remodeling projects, while reducing the term of construction. Therefore, this study aims to analyze the characteristics of Green Frame and its absolute term of construction, and compare the terms of frame work construction in apartment housing projects adopting different structural design approaches to illuminate their differences. In the end, Green Frame is found to be capable of reducing the term of construction in apartment housing projects. As the term of construction is a very critical element of a construction project, Green Frame will ultimately prove to be one of the key enablers to ensure the success of apartment housing construction projects.