• 천문학논총
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• 제20권1호
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• pp.21-27
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• 2005

We have been performing a wide-field photometric monitoring program, named SPVS (Short-Period Variability Survey), at the Bohyunsan Optical Astronomy Observatory (BOAO). The observation system consists of a small refracting telescope (D = 155 mm, f = 1050 mm) and a $2k{\times}3k$ CCD Camera. The field of view is $1.0^{\circ}{\times}1.5^{\circ}$. Detection limit is about V = 13 for short-period small amplitude variables such as ${\delta}$ Scuti-type pulsating stars, and about V = 15 for long-period large amplitude variables such as eclipsing binaries and RR Lyrae stars. The instrument is designed to be remote-controlled through internet. The primary purpose of this project is to search for variable objects in bright Galactic open clusters. We present results of test observations conducted towards NGC 7092.

• 천문학회지
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• 제40권4호
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• pp.153-155
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• 2007

We have analyzed H and $K_s$-band images of the Arches cluster obtained using the NIRC2 instrument on Keck with the laser guide star adaptive optics (LGS AO) system. With the help of the LGS AO system, we were able to obtain the deepest ever photometry for this cluster and its neighborhood, and derive the background-subtracted present-day mass function (PDMF) down to $1.3M_{\bigodot}$ for the 5"-9" annulus of the cluster. We find that the previously reported turnover at $6M_{\bigodot}$ is simply due to a local bump in the mass function (MF), and that the MF continues to increase down to our 50 % completeness limit ($1.3M_{\bigodot}$) with a power-law exponent of ${\Gamma}$ = -0.91 for the mass range of 1.3 < M/$M_{\bigodot}$ < 50. Our numerical calculations for the evolution of the Arches cluster show that the ${\Gamma}$ values for our annulus increase by 0.1-0.2 during the lifetime of the cluster, and thus suggest that the Arches cluster initially had ${\Gamma}$ of $-1.0{\sim}-1.1$, which is only slightly shallower than the Salpeter value.

• 여성건강간호학회지
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• 제10권4호
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• pp.291-300
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• 2004

Purpose: This study attempted to show the implications of obese female college students' weight control experiences and to use this as primary data for developing a nursing intervention. Method: The participants were 7 obese students who had tried losing weight at C College on Jeju Island. Their average age was 22 and BMI was $25.6kg/m^2$ on average. The data were collected from May 17th to July 6th 2004, and in-depth interviews were conducted with open-ended questions. Result: The analysis was conducted by Colaizzi's phenomenological method, and the analyzed results were categorized into 9 criteria, 22 theme clusters and 50 themes. The 9 criteria include withdrawal, desperation, self-restraint, relief, satisfaction, distraction, depression, regaining self-control and negligence of health. They tended to go through a weight gain loss cycle in a repetitive manner, and were faced with great physical and mental difficulties. In addition, they often went on a severely-strict diet without taking their health condition into consideration, which, in effect, causes various health problems. Conclusion: This study gives insights into the weight control experiences of obese female college students, and it shows developing more practical and effective nursing interventions are urgently needed.

• 대한간호학회지
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• 제31권2호
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• pp.180-193
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• 2001

The purpose of this study was to determine the meaning of the pain and experiences of elderly women with osteoarthritis, by adopting Colaizzi′s phenomenological method. The participants were 7 elderly women over the age of 65. They were selected using a theoretical sampling technique. The Data was collected by in-depth and open-ended interviews from Dec. 1. 1999. to Feb, 28. 2000. The length of the interviews varied from 120 minutes to 180 minutes. Data was recorded and analyzed by a constant comparative method. From the data, significant statements were extracted and then organized into 48 themes, which resulted in 15 clusters of themes and 6 categories. The final descriptions turned out to be valid through the interviewee′ validation process. Essential themes of the pain experiences emerged : "physical discomfortness(disturbances)", "negative state of mind", "influence of the death", "positive change in life", "Cause of pain perceived", and "change of their personal relationships". From these results, it was found that elderly women need nursing care based on a deep understanding of pain, and a reflection on their past is imperative to overcome their given situations. In conclusion, it is suggested that the care givers provide more support to solve the problems experienced by the elderly. Thus the researchers expect to provide understanding of older people and give basic data of holistic care for them.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.830-839
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• 2007

Pradimicins are potent antifungal antibiotics having an unusual dihydrobenzo[$\alpha$]naphthacenequinone aglycone substituted with D-alanine and sugars. Pradimicins are polyketide antibiotics produced by Actinomadura hibisca P157-2. The gene cluster involved in the biosynthesis of pradimicins was cloned and sequenced. The pradimicin gene cluster was localized to a 39-kb DNA segment and its involvement in the biosynthesis of pradimicin was proven by gene inactivation of prmA and prmB(ketosynthases $\alpha\;and\;\beta$). The pradimicin gene cluster consists of 28 open reading frames(ORFs), encoding a type II polyketide synthase(PKS), the enzymes involved in sugar biosynthesis and tailoring enzymes as well as two resistance proteins. The deduced proteins showed strong similarities to the previously validated gene clusters of angucyclic polyketides such as rubromycin, griseorhodin, and fredericamycin. From the pradimicin gene cluster, prmP3 encoding a component of the acetyl-CoA carboxylase complex was disrupted. The production levels of pradimicins of the resulting mutants decreased to 62% of the level produced by the wild-type strain, which indicate that the acetyl-CoA carboxylase gene would have a significant role in the production of pradimicins through supplying the extender unit precursor, malonyl-CoA.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권5호
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• pp.1932-1950
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• 2018

The paper proposes a code-clone detection method that gives the highest possible precision and recall, without giving much attention to efficiency and scalability. The goal is to automatically create a reliable reference corpus that can be used as a basis for evaluating the precision and recall of clone detection tools. The algorithm takes an abstract-syntax-tree representation of source code and thoroughly examines every possible pair of all duplicate tree patterns in the tree, while avoiding unnecessary and duplicated comparisons wherever possible. The largest possible duplicate patterns are then collected in the set of pattern clusters that are used to identify code clones. The method is implemented and evaluated for a standard set of open-source Java applications. The experimental result shows very high precision and recall. False-negative clones missed by our method are all non-contiguous clones. Finally, the concept of neighbor patterns, which can be used to improve recall by detecting non-contiguous clones and intertwined clones, is proposed.

• 임상간호연구
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• 제25권3호
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• pp.209-220
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• 2019

Purpose: A significant amount of public opinion about nurse bullying is expressed on the internet. The purpose of this study was to analyze the linkage structures among words extracted from comments on internet articles related to nurse workplace bullying using semantic network analysis. Methods: From February 2018 to April 2019, comments made on news articles posted to the Daum and Naver web portal containing keywords such as "nurse", "Taeum", and "bullying" were collected using a web crawler written in Python. A morphological analysis performed with Open Korean Text in KoNLPy generated 54 major nodes. The frequencies, eigenvector centralities, and betweenness centralities of the 54 nodes were calculated and semantic networks were visualized using the UCINET and NetDraw programs. Convergence of iterated correlations (CONCOR) analysis was performed to identify structural equivalence. Results: This paper presents results about March 2018 and January 2019 because these months had highest number of articles. Of the 54 major nodes, "nurse", "hospital", "patient", and "physician" were the most frequent and had the highest eigenvector and betweenness centralities. The CONCOR analysis identified work environment, nurse, gender, and military clusters. Conclusion: This study structurally explored public opinion about nurse bullying through semantic network analysis. It is suggested that various studies on nursing phenomena will be conducted using social network analysis.

• 벤처창업연구
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• 제16권4호
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• pp.195-209
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• 2021

서울시 전자상거래센터에서 실시한 2019-2020년 소셜미디어 이용실태 조사에 따르면 소비자 10명 중 5명이 소셜미디어를 통한 쇼핑경험이 있는 것으로 조사되었으며, The CMO Survey에서 2020년 코로나 펜데믹 기간에 실시한 조사에 따르면 전통적인 광고매체의 비용은 축소되고 소셜미디어에 대한 광고지출은 74%나 상승함으로써 소셜미디어가 더욱 중요한 마케팅 요소로 자리하고 있음을 나타내고 있다. 이만큼 소셜미디어의 이용자 증가와 그에 따른 기업의 마케팅 활동이 활발해지는 동안 소셜미디어에 대한 사용자의 이용동기, 만족도, 구매의도 등 다양한 마케팅 측면에서 연구되어져 왔으나, 온라인을 통해 농식품을 구매하는 상황에서 소비자들의 소셜미디어 이용빈도가 실제 구매행위에 어떠한 차이로 나타나는가에 대해 세분화 한 연구는 없었다. 본 연구는 온라인에서 농식품을 구매하는 소비자들을 대상으로 소셜미디어 이용빈도에 따라 유형별로 군집화하여 농식품 구매상황에서 보여지는 군집별 소비자특성의 차이를 파악하고자 하였으며, 제품관여도, 제품필요도, 온라인 구매채널 선택 등 3가지 농식품 구매상황에 대해 각 군집에서 나타나는 인구통계학적 분포, 지각된 위험, 식습관 라이프스타일 등의 소비자 특성을 확인하고 군집별 유형을 제시하였다. 이를 위해 245명의 소비자를 대상으로 소셜미디어 이용빈도 및 온라인 농식품 구매행태에 대한 설문 자료를 수집하였으며, 요인분석과 신뢰성 분석으로 측정변수의 타당성을 확보하였다. 소셜미디어 이용빈도에 따른 군집분석을 실시한 결과 3개의 군집으로 나뉘어졌으며, 첫번째 군집은 주로 개방형 소셜미디어를 사용하는 집단, 두번째 군집은 개방형 소셜미디어와 폐쇄형 소셜미디어, 온라인 쇼핑몰을 고루 사용하는 집단, 세번째 군집은 전반적으로 온라인 매체 사용량이 적은 집단으로 군집별 특성이 나타났다. 각 3개의 군집을 통해 온라인에서 농식품 구매시 제품관여도, 제품필요도, 구매채널 선택에 미치는 영향을 회귀분석을 통해 확인하였다. 회귀분석 결과 온라인에서 농식품을 구매하는 상황에서 보여지는 군집1의 특성은 소셜미디어나 온라인쇼핑몰에서 농식품을 구매하는데 거부감이 없는 지방에 거주하는 30대 남자로 소비자특성이 대표된다. 군집2의 특성은 주로 건강식품 구매에 관심이 많은 소비자로 소비자특성이 대표된다. 군집3의 경우는 온라인에서 제품을 구매하는 경우 품질과 가격을 많이 따져보고 구매하며, 온라인보다 오프라인 구매가 더 안심인 사람으로 소비자특성이 대표된다. 본 연구를 통해 소셜미디어 이용빈도에 따라 농식품 구매상황에서 나타나는 소비자 특성의 차이를 확인함으로써 소셜미디어 고객타겟팅과 고객세분화 등에 대한 마케팅 실무의 전략적인 판단에 도움을 줄 수 있을 것으로 판단된다.

• 천문학논총
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• 제30권3호
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• pp.821-832
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• 2015

NGC 1039 영역의 변광성 탐사로부터 7개의 ${\delta}$ Scuti형 변광성, 2개의 ${\gamma}$ Doradus형 변광성, 14개의 식쌍성 및 5개의 장지기형 불규칙 변광성을 찾았다. 이 중에서 3개를 제외한 나머지는 모두 새로 발견한 것이다. 이들 중 ${\delta}$ Scuti형 변광성 4개와 ${\gamma}$ Doradus형 변광성 2개 및 장주기형 불규칙 변광성 1개는 성단구성원일 가능성이 크다. 14개의 식쌍성 중에서 12개는 주기와 변광진폭 등을 구하였으며, 나머지 2개는 22일 관측 자료 중 하루치에서만 식 현상이 나타나서 EA형 식쌍성으로 보인다. B, V등급의 변광진폭을 같이 구한 식쌍성의 변광진폭비 $A_V/A_B$는 0.92이며, ${\delta}$ Scuti형 변광성의 결과를 이용한 0.75와 뚜렷이 구분된다. 5개의 장주기형 불규칙 변광성은 하나를 제외하고 나머지는 주기가 너무 길었고, 또한 주기성인지 알 수 없어서 밝기 변화만으로 변광성임을 알 수 있었다. 이 연구에서 찾은 변광성은 V등급이 10.84등급부터 16.30등급까지 분포하며, V등급의 변광진폭이 0.5등급 이상이면 16.3등급까지도 변광 여부를 확인할 수 있었다.

• 천문학논총
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• 제27권5호
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• pp.399-409
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• 2012

NGC 6871을 중심으로 시계열 관측한 Cyg OB3 성협영역에서 모두 15개의 단주기 변광성을 찾았다. 이들은 모두 국부나선팔에 속한 ${\delta}$ Scuti 형 변광성으로 보인다. 그림 5의 영연령주계열 상에서 밝은쪽에 속한 V1-V4는 분광형이 모두 A, F 형으로서 Cyg OB3 성협보다 먼 거리에 있는 ${\beta}$ Cephei 형 변광성이라기 보다는 국부나선팔의 앞쪽에 놓인 ${\delta}$ Scuti 형 변광성이었다. 15개의 ${\delta}$ Scuti 형 변광성 중에는 2개(V1과 V3)는 GCVS에 ${\delta}$ Scuti 형 변광성으로 분류되어 이미 알려진 변광성이고, 나머지는 모두 새로 발견한 것이다. 새로 발견한 변광성 중에는 한 개의 이중모드 ${\delta}$ Scuti 형 변광성(V3)과 2개의 HADS 변광성(V13과 V14)이 포함되었다. 시계열 관측과는 별도로 표준화 관측을 수행하여 관측 영역의 색-등급도를 얻었는데 그림 6에서 Massey etal.(1995)의 결과와 잘 맞았다.