• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.2
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• pp.67-71
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• 2019

In this paper, we derive a reference error probability performance in the environment where mobile satellite terminal is operated. When the satellite terminal moves, shadowing occurs due to the surrounding obstacles and the BER is lowered. We use the Lutz model simulating the environment in which mobile satellite terminals operate The Lutz model combines the Rician distribution with the Suzuki model. The error probability is derived from the numerical analysis of two distribution functions. The simulated results using the measured results in the Korean Peninsula forest area were similar to the BER results obtained using the Lutz model. Intuitively, the approximated results are similar to the measured results. Numerically, the BER error is about 3e-4 or less at an SNR of 30dB.

• Progress in Medical Physics
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• v.25 no.4
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• pp.281-287
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• 2014

The Winston Lutz test, which checks the accuracy of the isocenter for stereotactic radiosurgery (SRS), was performed with the commercial electronic portal imaging device (EPID). The usual Winston Lutz test with film was also performed for comparison with the test with EPID. The maximum difference in isocenter between the two methods was 0.32 mm. The Winston Lutz test using EPID is practical as it can reduce time and avoid human errors compared to the test with film.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.4
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• pp.103-111
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• 1985

Presented is a study on the determination of crack width and crack spacing in the reinforced concrete flexural members. The derivation of crack width and crack spacing is based on the recently developed cracking theory. The new prediction formulas for the crack widths and crack spacings are proposed. An experiment for the reinforced concrete beams was conducted to compare with the proposed formulas. The comparisons of the present prediction formulas with our tests and other test data show good agreement. The present crack width formula has been also compared with the well-known ACI formula originally proposed by Gergely & Lutz. It was found that the present crack width formula shows better correlation with test data than that of Gergely & Lutz.

• Journal of Arbitration Studies
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• v.27 no.3
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• pp.3-31
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• 2017

Legal tech is commonly considered as the use of software and technology in the process of providing legal services. It is disrupting the method in which legal services are traditionally rendered, and under the buzz word "e-arbitration" also extends to the area of international commercial arbitration. This article aims to give an introduction into the most pertinent issues in "e-arbitration", starting with an attempt at defining the term "e-arbitration" and with an overview of some of the service providers. It goes on to address the use of information technology in international arbitration and concludes with an analysis of key legal issues arising when various aspects of the arbitral process are commenced, conducted or concluded in digital form.

• Communications of the Korean Mathematical Society
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• v.33 no.1
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• pp.325-335
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• 2018

We prove every oriented compact cyclic 3-orbifold has a contact structure. There is another proof in the web by Daniel Herr in his uploaded thesis which depends on open book decompositions, ours is independent of that. We define overtwisted contact structures, tight contact structures and Lutz twist on oriented compact cyclic 3-orbifolds. We show that every contact structure in an oriented compact cyclic 3-orbifold contactified by our method is homotopic to an overtwisted structure with the overtwisted disc intersecting the singular locus of the orbifolds. In course of proving the above results we prove a classification result for compact oriented cyclic-3 orbifolds which has not been seen by us in literature before.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2003.06a
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• pp.143-146
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• 2003

• Progress in Medical Physics
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• v.17 no.4
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• pp.192-200
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• 2006

We evaluated the positional accuracy of the delivered beams to the target in a phantom by simulating the whole process of the radiation treatments Including CT scanning, planning and beam exposures with MLCs. For this purpose, a phantom was made to calibrate the alignment between the CT and the attached laser system. A new, convenient method was also devised to align the setup lasers in the treatment room. Film was used for the Identification of the delivered beam and analyzed with a homemade computer program. The positional differences between the target and the beam centers varied with the couch rotations. The accelerator we used showed a maximum discrepancy of 2.0 mm at the table angle of $295^{\circ}$. The same measurements based on the new isocenter from the Winston-Lutz test resulted in the maximum of 1.35 mm for all rotation angles. The evaluation of the differences between the target and the beam centers is useful for the treatment planning.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.28-28
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• 2005

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.323-324
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• 1999

• Proceedings of the Korean Society of Medical Physics Conference
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• 2006.08a
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• pp.62-62
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• 2006