• Journal of Astronomy and Space Sciences
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• 제31권3호
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• pp.187-197
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• 2014

We have investigated the dynamical stability of the proposed companions orbiting the Algol type short-period eclipsing binary SW Lyncis (Kim et al. 2010). The two candidate companions are of stellar to substellar nature, and were inferred from timing measurements of the system's primary and secondary eclipses. We applied well-tested numerical techniques to accurately integrate the orbits of the two companions and to test for chaotic dynamical behavior. We carried out the stability analysis within a systematic parameter survey varying both the geometries and orientation of the orbits of the companions, as well as their masses. In all our numerical integrations we found that the proposed SW Lyn multi-body system is highly unstable on time-scales on the order of 1000 years. Our results cast doubt on the interpretation that the timing variations are caused by two companions. This work demonstrates that a straightforward dynamical analysis can help to test whether a best-fit companion-based model is a physically viable explanation for measured eclipse timing variations. We conclude that dynamical considerations reveal that the proposed SW Lyncis multi-body system most likely does not exist or the companions have significantly different orbital properties from those conjectured in Kim et al. (2010).

• 한국콘텐츠학회논문지
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• 제22권1호
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• pp.380-390
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• 2022

본 연구는 상상 친구가 등장하는 그림책에서 주인공에게 상상 친구가 어떠한 기능을 하는지 알아보고자 하였다. 이를 위해 국내에서 출판된 상상 친구가 등장하는 총 26권의 그림책을 대상으로 내용분석법을 사용하여 주인공과 상상 친구의 관계 속에서 나타나는 상상 친구의 기능을 분석하였다. 연구결과 상상 친구는 그림책 속에서 주인공의 상황과 필요에 따라 놀이동반자(77%), 돌봄 조언자(42%), 동행자(42%), 다른 자아(38%), 소망 실현자(23%), 정서 공유자(23%), 정서 조절자(19%)의 다양한 기능을 수행하는 것으로 나타났다. 분석 그림책에서 대부분 2-3개의 기능이 수행되고 있었으며 연구결과 나타난 7가지 기능을 주인공과의 관계적 측면에서 살펴보았을 때 수평적 관계, 수직적 관계, 다른 자아의 세 가지 유형으로 나타났다. 그림책에서 묘사되고 있는 상상 친구는 주인공의 소망을 실현시키고, 돌봐주고 정서조절을 하도록 도움을 주는 존재이기도 하지만, 함께 놀고, 마음을 나누는 동등한 관계와 다른 나를 투영하며 함께 하는 좋은 친구의 모습으로 나타났다.

• 천문학회보
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• 제39권2호
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• pp.86.1-86.1
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• 2014

Two substellar companion candidates with planetary mass, around a T-Tauri star in the ${\rho}$ Ophiuchi star-forming region, are discovered by results of Subaru Telescope's near-infrared imaging. Candidates are separated by 1400au and 500au. If these candidates were real companions, they are the widest-orbit and the lowest mass planetary-mass companions(PMCs) candidates. This discovery may suggest that PMCs form via extreme case of cloud core fragmentation for multiple stars. And also stellar disk are imaged by HiCIAO, hight contrast instrument for exoplanets and disks, with Subaru Telescope. This could be the first case, which imaged both of planetary mass companions and disk around same star. Even two companions candidates are not bounded around the star, they still could be one of the lowest mass objects. In this presentation, I will discuss about observations and confirmations of these objects, and the latest results about their properties.

• 대한수학회보
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• 제42권2호
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• pp.213-230
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• 2005

Companions of Ostrowski's integral inequality for absolutely continuous functions and applications for composite quadrature rules and for p.d.J.'s are provided.

• 천문학회보
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• 제39권2호
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• pp.52-52
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• 2014

It is widely accepted that the evolution of galaxies is accelerated in dense environments. According to recent studies, however, the evolution by direct interactions between galaxies is known to be most active in a galaxy group rather than in a galaxy cluster. In particular, the central galaxy in a group is closely related to its satellites in the properties such as morphology, color and star formation rate, because those galaxies evolve together in a small-scale environment. Currently, however, it is not yet studied well whether such conformity between bright galaxies and their faint companions remains after a galaxy group falls into a galaxy cluster. Recently, Lee et al. (2014) have found that the colors of bright galaxies show a measurable correlation with the mean colors of faint companions around them in WHL J085910.0+294957, a galaxy cluster at z = 0.3, which may be the vestige of infallen groups in the cluster. As a follow-up study, we study Abell 2744, an ongoing cluster-cluster merger at z = 0.308, using the HST Frontier Fields Survey data. The cluster members are selected based on the distributions of color, size and concentration along magnitude. The correlation in color between bright galaxies and their companions is not found in the full area of Abell 2744. However, when the area is limited to the southeastern part of the Abell 2744 image, the mean color of faint companions shows marginal dependence (> $2{\sigma}$ to Bootstrap uncertainties) on the color of their adjacent bright galaxy. We discuss the implication of these results, focusing on their dependence on local environments.

• 대한가정학회지
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• 제35권2호
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• pp.33-47
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• 1997

The purpose of the study is to examine the differences between rural and urban in the factors and the level of stress in adolescent, inner control and communication with parents. Also, It is to research the influence of environmental variables, inner control and communication with parents on adolescent's stress in sides of rural and urban. Therefore, I provide needed data in instructing students. For the data set, academic high school students in second grade in a town for rural and Su-Seung gu, Dal-Sugu, chung gu in Dae-gu for urban were chosen. The data were analyzed with the frequency, percentage, factor analysis Mean, S.D, reliability, t-test, regression in use of Spss PC+ Program. The main results are as follow. First, for rural students, stress level is displayed studies, future0affair, life-attitude, companions, self-assurance and home life in order by lower sphere. For urban students, it is displayed future-affair, studies, life-attitude, companions, self-assurance and home life in order by lower shpere. In case of rural "I don't know effective study method" is highly displayed by factors. In case of urban. "I am tired of a competitive life" is highly displayed. The mean of stress level is 3.22 for rural and 3.07 for urban. The differences between rural and urban are showed in self-assurance, studies and companions. Finally when we see the stress generally the stress level is higher in rural high school students than in urban high school students. Second, rural students are lower displayed than urban students in inner control and communication with parents. There is no difference urban students in inner control and communication with parents. There is no difference in communication with a mother. third, influential variables on stress level are inner control, communication with parents, satisfaction with companions and school life as environmental variables in sides of rural and urban. Physical condition is added for rural and sex for urban Finally we get the result that stress level is high in low inner control, poor communication with parents, bad companions and unsatisfied school life for both rural and urban. Bad physical condition for rural and female for urban are added.

• ETRI Journal
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• 제29권3호
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• pp.311-321
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• 2007

In this paper, we propose a user-centric conflict management method for media services which exploits personal companions for the harmonious detection and resolution of service conflicts. To detect conflicts based on the varying characteristics of individual users, the proposed method exploits the unified context describing all users attempting to access media services. It recommends and mediates users' preferred media contents through a shared screen and personal companions to resolve the detected conflicts. During the recommendation, a list of preferred media contents is displayed on the shared screen, and a personally preferred content list is shown on the user's personal companion comprising the selection of media contents. Mediation assists the selection of a consensual service by gathering the users' selections and highlighting the common media contents. In experiments carried out in a ubiHome, we observed that recommendations and mediation are useful in harmoniously resolving conflicts by encouraging user participation in conflict situations.

• Journal of Astronomy and Space Sciences
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• 제29권1호
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• pp.63-67
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• 2012

Observations with milliarsecond resolution using the Navy Optical Interferometer have been obtained for a number of stellar systems which include high-mass binaries, eclipsing binaries, and radio stars. These observations also reveal the previously unseen companions in single-lined spectroscopic binaries via directly measured flux ratios. We will present examples of published and ongoing research efforts of these systems to illustrate how an optical interferometer contributes to our knowledge of stars, their environment, and companions. These studies include a conclusive revealing of the previously unseen companion in the single-lined binary ${\Phi}$ Herculis, the direct determination of orbital parameters in the wide and close orbits of Algol, and revealing the orbit of ${\beta}$ Lyrae with spatially resolved images of the $H{\alpha}$ emission.

• 대한수학회논문집
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• 제20권3호
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• pp.487-503
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• 2005

Some companions of Gruss inequality in 2-inner product spaces and applications for determinantal integral inequalities are given.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권10호
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• pp.4766-4786
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• 2016

Looking for missing companions who are out of touch in public places might suffer a long and painful process. With the help of mobile crowdsourcing, the missing person's location may be reported in a short time. In this paper, we propose MissingFound, an assistant system that applies mobile crowdsourcing for finding missing companions. Discovering valuable users who have chances to see the missing person is the most important task of MissingFound but also a big challenge with the requirements of saving battery and protecting users' location privacy. A customized metric is designed to measure the probability of seeing, according to users' movement traces represented by WiFi RSSI fingerprints. Since WiFi RSSI fingerprints provide no knowledge of users' physical locations, the computation of probability is too complex for practical use. By parallelizing the original sequential algorithms under MapReduce framework, the selecting process can be accomplished within a few minutes for 10 thousand users with records of several days. Experimental evaluation with 23 volunteers shows that MissingFound can select out the potential witnesses in reality and achieves a high accuracy (76.75% on average). We believe that MissingFound can help not only find missing companions, but other public services (e.g., controlling communicable diseases).