• 한국정보처리학회논문지
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• 제6권3호
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• pp.571-579
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• 1999

A Macro-Star graph which has a star graph as a basic module has node symmetry, maximum fault tolerance, and hierarchical decomposition property. And, it is an interconnection network which improves a network cost against a star graph. A matrix star graph also has such good properties of a Macro-Star graph and is an interconnection network which has a lower network cost than a Maco-Star graph. In this paper, we propose a method to embed between a Macro-Star graph and a matrix star graph. We show that a Macro-Star graph MS(k, n) can be embedded into a matrix star graph MS\ulcorner with dilation 2. In addition, we show that a matrix star graph MS\ulcorner can be embedded into a Macro-Star graph MS(k,n+1) with dilation 4 and average dilation 3 or less as well. This result means that several algorithms developed in a star graph can be simulated in a matrix star graph with constant cost.

• 천문학논총
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• 제28권3호
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• pp.37-54
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• 2013

China and Korea have a long history of star charts, dating from the prehistoric period. Historically, Korean astronomy has been deeply influenced by China over the last two thousand years, particularly on constellation system. Therefore, Chinese and Korean traditional star charts have many similarities in terms of shape of constellation, number of star, and so forth. Korean star charts, however, have lots of unique characteristics distinguishing from Chinese ones, such as, size of star and position of constellation. Overall knowledge of the Chinese star chart is required to study the Korean star chart. In this paper, I focus on introducing selected star charts in China and Korea. Although this review is very limited, I hope that this paper is helpful in research in the field of historical astronomy.

• 패션비즈니스
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• 제12권6호
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• pp.138-151
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• 2008

This study aims at providing comprehensive data which would be helpful to establish a web shopping mall by analyzing the structure of web fashion star shops which have recently emerged as a result of advances in digital technology and communication. For the purpose of analyzing VMD strategy used in web fashion star shop, we adopt both of the documental and empirical research methods, based on which we examine the concept of E-commerce and current business situation of web fashion star shop industry, and then analyze the main page, product category page and product detail page in a star shop featured by a male pop star within a web shopping mall. According to our analysis of the structure of web fashion star shop, in case of open market, a banner with star's image on it leads to star shop when people click on the link of the banner, and in case of independent mall, they show each star's unique style in the main page. Product category page is linked to each product detail page which presents items of various fashion coordinates, satisfying needs of consumers to follow star's trendy fashion sense.

• 천문학회지
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• 제29권1호
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• pp.19-30
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• 1996

We have examined consequences of strong tidal encounters between a neutron star and a normal star using SPH as a possible formation mechanism of isolated recycled pulsars in globular clusters. We have made a number of SPH simulations for close encounters between a main-sequence star of mass ranging from 0.2 to 0.7 $M_\bigodot$ represented by an n=3/2 poly trope and a neutron star represented by a point mass. The outcomes of the first encounters are found to be dependent only on the dimensionless parameter $\eta'{\equiv}(m/(m+ M))^{1/2}(\gamma_{min}/R_{MS})^{3/2}(m/M)^{{1/6)}$, where m and M are the mass of the main-sequence star and the neutron star, respectively, $\gamma_{min}$ the minimum separation between two stars, and $R_{MS}$ the size of the main-sequence star. The material from the (at least partially) disrupted star forms a disk around the neutron star. If all material in the disk is to be acctreted onto the neutron star's surface, the mass of the disk is enough to spin up the neutron star to spin period of 1 ms.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.598-600
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• 1993

Gold Star Cable Co. have developed Condenser Bushing Equipment for high voltage apparatus. The basic design theory and manufacture procedure are introduced in this paper.

• 천문학논총
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• 제30권2호
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• pp.573-576
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• 2015

Recent discovery of $2M_{\odot}$ neutron stars in white dwarf-neutron star binaries, PSR J1614-2230 and PSR J0348+0432, has given strong constraints on the maximum mass of neutron stars. On the other hand, all well-measured neutron star masses in double neutron star binaries are still less than $1.5M_{\odot}$. These observations suggest that the neutron star masses in binaries may depend on the evolution process of neutron star binaries. In addition, recent works on LMXB (low-mass X-ray binaries) provides us the possibility of estimating the masses and radii of accreting neutron stars in LMXBs. In this talk, we discuss the implications of recent neutron star observations to the neutron star equation of states and the related astrophysical problems. For the evolution of neutron star binaries, we also discuss the possibilities of super-Eddington accretion onto the primary neutron stars.

• 한국항공우주학회지
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• 제34권2호
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• pp.96-100
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• 2006

본 논문은 위성의 자세정보를 획득하는 센서로서 과학기술위성2호에 장착하기 위해 개발 중인 이중 머리 별 추적기를 소개한다. 대부분의 별 센서는 위성의 한쪽 방향만 지향하기 때문에 태양 및 지구 영역으로 지향할 경우 별 인식이 불가능하다. 그래서 시스템은 두개의 카메라를 직각의 방향으로 지향하여 동시에 두개의 영상을 입력 받고 하나의 영상에서 별 인식을 실패할 경우 다른 영상에서 별 인식을 수행하여 별 인식률을 높이도록 구현하였다. 논문에서는 이중머리 별 추적기의 시험모델을 소개하고 별 인식 및 별 추적 알고리즘을 제안하였다.

• 대한수학회논문집
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• 제11권4호
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• pp.1067-1075
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• 1996

We show that every ultrapure space is weakly star reducible, and that every countably compact weakly star reducible space is compact. We also pose open problems.

• Journal of Astronomy and Space Sciences
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• 제12권2호
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• pp.256-264
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• 1995

This report presents the development procedure and the results of a prototype star sensor which can be used as one of the attitude sensors of the KITSAT-3. The star sensor is a major attitude sensor that can determine the 3-axis attitude information, by comparing between star corrdinates in the star catalog and the measured corrdinates. The 2 dimensional CCD camera is used for measuring the star corrdinates and the DSP(Digital Signal Processor) technology is applied to the image and signal processing. Using the prototype star sensor with thermoelectri cooling technique, we have succesfully obtained the star images around 4th magnitude at Sobaeksan Astronomy Observatory minimizing night sky effect.

• Journal of Astronomy and Space Sciences
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• 제31권3호
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• pp.205-214
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• 2014

In this study, a star identification algorithm which utilizes pivot patterns instead of apparent magnitude information was developed. The new star identification algorithm consists of two steps of recognition process. In the first step, the brightest star in a sensor image is identified using the orientation of brightness between two stars as recognition information. In the second step, cell indexes are used as new recognition information to identify dimmer stars, which are derived from the brightest star already identified. If we use the cell index information, we can search over limited portion of the star catalogue database, which enables the faster identification of dimmer stars. The new pivot algorithm does not require calibrations on the apparent magnitude of a star but it shows robust characteristics on the errors of apparent magnitude compared to conventional pivot algorithms which require the apparent magnitude information.