• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.10
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• pp.1042-1048
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• 2008

Disc brake noise is an important customer satisfaction and warranty issue for many manufacturers as indicated by technical literature regarding the subject coming from Motor Company. This research describes results of a study to assess disk brake squeal propensity using finite element methods and optimal technique (Kriging). In this study, finite element analysis has been performed to determine likely modes of brake squeal. This paper deals with friction-induced vibration of disc brake system under contact friction coefficient. A linear, finite element model to represent the floating caliper disc brake system is proposed. The complex eigen-values are used to investigate the dynamic stability and in order to verify simulations which are based on the FEM model. In this paper, Kriging from among the meta-modeling techniques is proposed for an optimal design scheme to reduce the brake squeal noise.

• Korean Journal of Materials Research
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• v.13 no.3
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• pp.144-149
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• 2003

This study shows an experimental investigation of a reversible nano colloidal damper, which is statically loaded. The porous matrix is composed from silica gel (labyrinth or central-cavity architecture), coated by organo-silicones substances, in order to achieve a hydrophobic surface. Water is considered as associated lyophobic liquid. Reversible colloidal damper static test rig and the measuring technique of the static hysteresis are described. Influence of the pore and particle diameters, particle architecture and length of the grafted molecule upon the reversible colloidal damper hysteresis is investigated, for distinctive types and mixtures of porous matrices. Variation of the reversible colloidal damper dissipated energy and efficiency with temperature, pressure, is illustrated. As a result, he proposed nano damper is effective one, which can be replaced the conventional damper.

• IMMUNE NETWORK
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• v.13 no.5
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• pp.177-183
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• 2013

Development of nano-sized carriers including nanoparticles, nanoemulsions or liposomes holds great potential for advanced delivery systems for cancer immunotherapy, as such nanostructures can be used to more effectively manipulate or deliver immunologically active components to specific target sites. Successful development of nanotechnology based platform in the field of immunotherapy will allow the application of vaccines, adjuvants and immunomodulatory drugs that improve clinical outcomes for immunological diseases. Here, we review current nanoparticle-based platforms in the efficacious delivery of vaccines in cancer immunotherapy.

• Korean Institute of Interior Design Journal
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• v.14 no.6 s.53
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• pp.29-36
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• 2005

The original members of the De Stijl group, formed in neutral Holland during the First World War, included the painters Piet Mondrian, Bart van Leck and Theo van Doesburg, and the architects J.J.P. Oud and Jan Wils. The aim of the group was to create a language of form and color applicable to every sphere of modern life. The means of expression selected by the De Stijl artists was rigorously restricted, using only vertical and horizontal lines with the right-angle created where they cross, and for color, black, white and the primaries- red, yellow and blue. Of these simple elements consisted the compositions painted by Mondrian and van Doesburg during the years around the end of the First World War, and the famous red-blue chair made by Gerrit Rietvelt in 1917. They did share a common influence, Cubism, and they both emphasized contemporaneity. Otherwise they were quite different movements, both in theory and practice, except lot one further point of similarity.

• Journal of Korean Neurosurgical Society
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• v.29 no.6
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• pp.836-840
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• 2000

Intramedullary spinal hemagioblastomas usually develope in cervical or thoracic region of spinal cord, but rarely in conus medullaris. We report a case of hemangioblastoma developed in conus medullaris. The 19-year-old male patient presented with slowly progressing low back pain and paresthesia of both legs. MRI and spinal angiography revealed a well-vascularized mass lesion in the conus medullaris with syrinx formation. Total excision of hemangioblastoma was achieved via posterior approach. Postoperatively, patient's walking difficulty was worsened transiently, but it was improved at discharge.

• International Commerce and Information Review
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• v.1 no.1
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• pp.41-55
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• 2008

The Visa Waiver Program of the United States increases the number of Korean tourists to the US but lso affects the number of the US tourists to Korea. One of the most important factors in the tourism industry is the increase in the demand for tourism and other related services. In this regard, the VWP is expected to be a new opportunity which generates such demands. It should be reminded that the sustainable development in the industry is essential rather than limiting to the effects of the VWP. Transportation and communication has recorded unbelievable advancement which will be continued in the future.

• Publications of The Korean Astronomical Society
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• v.18 no.1
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• pp.111-133
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• 2003

Most radio astronomy issues at WRC-03 (World Radiocommunication Conference-03) revolved around satellite downlink allocations, particularly to NGSO (Non-Geostationary Satellite Orbit) satellite systems, in bands adjacent to or close to a radio astronomy frequency band. Out of a total of 50 agenda items, ten were of interest to radio astronomers. This paper provides some details about the important outcome of the radio astronomy related issues at the WRC-03.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2265-2271
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• 1994

With the improvement of standard of living, requirement for comfortable and quiet environment has been increased and, therefore, there has been a many researches for active noise reduction to overcome the limit of passive control method. In this study, active noise control is performed in a duct system using intelligent control technique which needs not decide the coefficients of high order filter and the mathematical modeling of a system. Back propagation algorithm is applied as an intelligent control technique and control system is organized to exclude the error microphone and high speed operational device which are indispensable for conventional active noise control techniques. Furthermore, learning is performed by organizing acoustic feedback model, and the effect of the proposed control technique is verified via computer simulation and experiment of active noise control in a duct system.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.6
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• pp.405-412
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• 2002

Recently, regulations of the government and concerns of people give rise to the interest in exhaust and intake noise of passenger car as much as other vehicles. In these demands, performance prediction software with hybrid method was developed at first. Secondly, robust design was used for improving the noise reduction capacity of intake system with the performance prediction software. On the basis of the existing design, length and radios of each component that was thought to effect on the capacity of intake system was selected. The factors were arranged by using L18 table of orthogonal array and optimum value was obtained.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.10
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• pp.2523-2532
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• 1994

In this paper, active noise control is performed in a duct system using the periodic pulse train which corresponds to the periodic component of noise source as a reference signal. Control algorithm applied in this study is possible to eliminate the acoustic feedback which occurs in the conventional filtered-x and filtered-u LMS algorithm by using electrical reference signal and has the fast adaptation speed with low filter orders by using synchronous sampling method is discussed via computer simulations and experiments of case studies such as frequency modulation, amplitude modulation and frequency differency between source signal and reference signal.