• Journal of the Korean Data and Information Science Society
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• v.26 no.1
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• pp.77-87
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• 2015

Parrondo paradox is the counter-intuitive phenomenon where two losing games can be combined to win or two winning games can be combined to lose. In this paper, we consider an ensemble of players, one of whom is chosen randomly to play game A' or game B. In game A', the randomly chosen player transfers one unit of his capital to another randomly selected player. In game B, the player plays the history-dependent Parrondo game in which the winning probability of the present trial depends on the results of the last two trials in the past. We show that Parrondo paradox exists in this redistribution model of the history-dependent Parrondo game.

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.3 s.22
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• pp.73-82
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• 2005

This paper describes shock waveform synthesis methods for a shock response spectnlm over a short time interval with which intereference between parts within a test item is increased to perform a sufficient shock test for damage or malfunction which may be caused by the interference between parts, and a digital filter for obtaining a shock response history required for the shock waveform synthesis and a digital inverse filter for restoration by inversely using the digital filter. The time at which the maximax value occurs in the response history is detected in order to establish a delay time which is one of the parameters in the wavelet, on the condition that the natural frequency of SDOF system with a Q (quality factor) of 10 equals to the wavelet frequency of the zero delay wavelet input. A shock response spectrum over a short time interval and an abrupt change in the acceleration for an instant are illustrated as features of the synthesized waveform.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.39.2-39.2
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• 2020

Based upon the previous heritage in the complete development of the infrared imaging spectrometer, NISS (Near-infrared Imaging Spectrometer for Star formation history) onboard NEXTSat-1, we are participating in the NASA MIDEX mission (PI Institute: Caltech), the all-sky infrared spectro-photometric surveyor SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer). The SPHEREx will provide us the first all-sky infrared spectro-photometric data set to probe the origin of our Universe, to explore the origin and evolution of galaxies, and to explore whether planets around other stars could harbor life. After the SPEHREx have passed the PDR (Preliminary Design Review) on this September, the fabrication of flight hardware will be started soon. As an international partner, KASI takes part in the hardware development, the operation and the science for the SPHEREx. Here, we report the status of the SPHEREx project and the progress in the Korean participation.

• Development and Reproduction
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• v.18 no.4
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• pp.259-266
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• 2014

The egg development and early life history of Korean spotted sleeper, Odontobutis interrupta which is Korean endemic species from Sora-choen was investigated. The Korean spotted sleeper were caught at Sora-myeon, Yeosu-si, Jeollanamdo, from Korea at May in 2014. The fertilized eggs were $4.23{\pm}0.05mm$ in long diameter and had oil globules. Hatching time of the embryo began about 442 hr 14 min after fertilization under water temperature of $19.5^{\circ}C$. The newly hatched larvae were $4.27{\pm}0.35mm$ in total length and their anus were not yet opened. 3 days after hatching postlarvae was measured $6.20{\pm}0.11mm$ in total length. 10 days after hatching postlarvae was measured $6.69{\pm}0.14mm$ in total length.

• Journal for History of Mathematics
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• v.33 no.3
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• pp.135-154
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• 2020

This paper tries to show the formation of 'Kyungpook School' that is a nickname given to mathematicians of Kyungpook National University (KNU). In the early period, the role of professor Park Jung-gi was the most important drive to set the research tradition. He made Korea's first english journal in mathematics, Kyungpook Mathematical Journal KMJ which became a cornerstone for students to join the international academic community. Professor Ki U-hang published the most amount of papers in Korea in 1970s and became a role model for young scholars. In this background, KNU's Topology and Geometry Research Center at KNU was chosen as the only Science Research Center in mathematics in 1989, and KNU's mathematicians could get a long-period support for capable mathematics researchers' community.

• Journal for History of Mathematics
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• v.28 no.3
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• pp.133-149
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• 2015

Arrivals of Hilbert and Minkowski at $G\ddot{o}ttingen$ put mathematical science there in full flourish. They further extended its strong mathematical tradition of Gauss and Riemann. Though Riemann envisioned Finsler metric and gave an example of it in his inaugural lecture of 1854, Finsler geometry was officially named after Minkowski's academic grandson Finsler. His tool to generalize Riemannian geometry was the calculus of variations of which his advisor $Carath\acute{e}odory$ was a master. Another $G\ddot{o}ttingen$ graduate Busemann regraded Finsler geometry as a special case of geometry of metric spaces. He was a student of Courant who was a student of Hilbert. These figures all at $G\ddot{o}ttingen$ created and developed Finsler geometry in its early stages. In this paper, we investigate history of works on Finsler geometry contributed by these frontiers.

• Journal for History of Mathematics
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• v.27 no.5
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• pp.313-327
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• 2014

Based on the importance and the necessity of the study on history of mathematics and mathemtics education using history of mathematics for finding the cultural identity and values of our traditional mathematics, we refer to two types of teaching and learning methods utilizing 'WonYongSamBangHoGu', the second theme of 'SanSulGwanGyeon' written by Lee Sang Hyuk. First, we present various cases of 'WonYongSamBangHoGu' constructed utilizing kind of mathematics learning software, GeoGebra by high school freshmen belonging to the Education Centers for the Gifted in Seoul Science Park. Second, We modernly reinterpret the questions contained in 'WonYongSamBangHoGu' and show several developed items using it.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.8 no.1
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• pp.11-30
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• 2004

Access Control is one of essential branches to provide system's security. Depending on what standards we apply, in general, there are Role-based access control, History-based access control. The first is based on subject's role, The later is based on subject's history. In fact, RBAC has been implemented, we are using it by purchasing some orders through the internet. But, HBAC is so complex that there will occur some errors on the system. This is more and more when HBAC is used with other access controls. So HBAC's formalization and model which are general enough to encompass a range of policies in using more than one access control model within a given system are important. To simplify these, we design the mathematical model called non-access structure. This Non-access structure contains to historical access list. If it is given subjects and objects, we look into subject grouping and object relation, and then we design Non-access structure. Then we can determine the permission based on history without conflict.

• Journal of TMJ Balancing Medicine
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• v.1 no.1
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• pp.9-12
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• 2011

Objectives: Functional Cerebrospinal Therapy (FCST) is a rather new physiologic therapeutics. It has passed about two decades since its basic idea was founded. This study briefly reviewed its early history. Methods: The first FCST patient was a stroke patient in the year 1992. Basic ideas of FCST was devised one by one and later developed into a systematic clinical application. The first official lecture was held in the year 2004. Yinyang balance in the meridian-system-based network over the whole body was a mainstay idea. Results: As other stories on newly-developed therapeutics, there was an effort to make a breakthrough for difficult clinical problems, and followed by a creative initial idea along with incessant refinement in the early history of FCST. Conclusions: Patient-centered approaches was a mainspring in the development and refinement of FCST. History of FCST hereafter may well follow the trace.

• Fisheries and Aquatic Sciences
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• v.11 no.3
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• pp.177-181
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• 2008

Glyceraldehyde 3-phosphate dehydrogenase(GAPDH) is a key enzyme for carbohydrate metabolism in most living organisms. Recent reports and our own searches of teleost species in publicly available genomic databases have identified at least two distinct GAPDH genes in a given species. The two GAPDH genes are located on the same chromosome in teleosts, whereas they are located on the different chromosomes in mammals. Thus, we reconstructed a phylogenetic tree to better understand the evolutionary history of the GAPDH genes in the vertebrate lineage. Our phylogenetic analysis revealed unambiguously that the two GAPDH genes of teleosts are phylogenetically closely affiliated to one of the cytosolic GAPDH and spermatogenic GAPDH-S of mammals. This indicates that the two paralogous GAPDH genes shared a common ancestor and subsequently underwent a gene duplication event during early vertebrate evolution. However, GAPDH-S of teleosts showed significant differences in the polypeptide residues and tissue distribution of its mRNA transcripts from that of mammals, implying they have undergone a different history of functionalization.