• 한국정보과학회논문지:소프트웨어및응용
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• 제30권5_6호
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• pp.414-429
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• 2003

시스템 개발 시 복잡성을 감소시키고 개발 비용과 기간을 단축하기 위하여 컴포넌트 기반 개발(CBD)이 산업계에서 보편화 되고 있다. 그러나, 현재 대표적인 CBD는 한 회사나 하나의 어플리케이tus에 의존적인 컴포넌트를 개발하고 있다[1,2]. 따라서 어떤 도메인의 여러 패밀리에서 컴포넌트를 재사용하기 위한 컴포넌트 가변성이 강조 되고 있다. 하지만, 컴포넌트 가변성의 정의나 유형에 대해 구체적으로 제시된 연구가 미흡하여, 컴포넌트의 주 목적인 재사용 측면보다. 유지보수 목적의 컴포넌트가 개발되고 있다[3]. 본 논문에서는 컴포넌트의 재사용성을 높이기 위하여, 컴포넌트 특징을 반영한 컴포넌트 가변성을 정형적으로 정의한다. 또한, 기존의 컴포넌트 가변성으로 인식된 논리 가변성을 명확하게 정의하고, 추가로 3가지 가변성 유형을 제시함으로써, 컴포넌트에서 존재하는 모든 가변성 유형을 제시한다. 컴포넌트 커스터마이제이션시에 가변성의 경우의 수를 예측, 확인 할 수 있는 컴포넌트 가변성 Scope를 제시한다. 컴포넌트 개발에 있어서 이러한 기법을 적용함으로써, 여러 패밀리 멤버에서 재사용 할 수 있는 고품질의 컴포넌트 개발을 지원 할 수 있다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1435-1440
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• 2009

Geotechnical variability is a complex feature that results from many independent sources of uncertainties, and is mainly affected by inherent variability and measurement errors. This study evaluates the coefficient of variation (COV) of soil properties at Song-do region in Korea for evaluating inherent soil variability. Since soil variability is sensitive to soil layers and soil types, the COVs by soil layers (reclaimed layer and marine layer) and the COVs by soil types (clay and silt) were separately evaluated. It is observed that geotechnical variability of marine layer and clay is relatively smaller than that of reclamation layer and silt.

• 천문학회보
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• 제37권1호
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• pp.58.1-58.1
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• 2012

We present a comprehensive re-analysis of stellar photometric variability in the field of open cluster M37, using our new high-precision light curves. This dataset provides a rare opportunity to explore different types of variability between short (-minutes) and long (-one month) time-scales. To investigate the variability properties of -30,000 objects, we developed new algorithms for detecting periodic, aperiodic, and sporadic variability in their light curves. About 7.5% (2,284) of the total sample exhibits convincing variations that are induced by flares, pulsations, eclipses, starspots and, in some cases, unknown causes. The benefits of our new photometry and analysis package are evident. The discovery rate of new variables is increased by 63% in comparison with the existing catalog of variables, and 51 previously identified variables were found to be false positives resulting from time-dependent systematic effects. Based on extended and improved catalog of variables, we will review the basic properties (e.g., periodicity, amplitude, type) of the variability and how different they are for different spectral types and for cluster memberships.

• 대한수학교육학회지:수학교육학연구
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• 제20권4호
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• pp.493-509
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• 2010

학교수학에서 학생들의 통계적 사고를 개발하고 향상시키기 위한 수단으로 많은 선행 연구들은 변이성에 주목하고 변이 추론을 지도할 것을 제안한다. 이 논문에서는 변이성과 변이 추론을 지도하는데 필요한 지식을 살펴보았다. 이를 위해 변이성의 근원은 무엇인지, 변이성에 대한 대처 방식은 무엇인지, 변이성의 유형에는 어떠한 것이 있는지, 변이성을 어떻게 인지하게 되는지, 변이성과 문제해결과는 어떠한 관련이 있는지 살펴보았다. 연구 결과 통계적 활동에서 변이성의 근원과 변이성에 어떻게 대처할 것인지에 대한 토론은 학생들로 하여금 다양한 유형의 변이성을 인지하도록 하고 이후 통계적 활동에 적극적으로 참여하도록 하는 동기부여가 될 수 있음을 확인하였다. 또한 자료의 표현 지도에서 변이 추론을 강조하는 것이 통계교육에 좀더 부합하는 방향임을 확인하였다. 학교수학에서 다루어지는 변이성의 유형, 그리고 문제해결과 변이성에 대한 검토는 내용요소 중심의 통계교육과정 배열에 대한 반성의 기회를 제공하였다.

• 천문학회보
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• 제46권1호
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• pp.57.2-57.2
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• 2021

Variability in Young Stellar Objects (YSOs) can be caused by time-dependent accretion rates, geometric changes in the circumstellar disks, the stochastic hydromagnetic interactions between stellar surfaces and inner disk edges, reconnections within the stellar magnetosphere, and hot/cold spots on stellar surfaces. We uncover ~1400 variables from a sample of ~5300 YSOs in nearby low-mass star-forming regions using mid-IR light curves obtained from the 5.5-years NEOWISE All Sky Survey. The mid-IR variability traces a wide range of dynamical, physical, and geometrical phenomenon. We classify six types of YSO variability based on their light curves: secular variability (Linear, Curved, Periodic) and stochastic variability (Burst, Drop, Irregular). YSOs in earlier evolutionary stages have higher fractions of variables at all types and higher amplitudes for the variability. Along with brightness variability, we also find a diverse range of secular color variations, which can be attributed to a competitive interplay between the variable accretion luminosity of the central source and the variable extinction by material associated with the accretion process. We compare the variability of known FUors/EXors and VeLLOs/LLSs, which represent two extreme ends (burst versus quiescent) of the episodic accretion process; FUors/EXors have a higher fraction of variables (65%) than VeLLOs/LLSs (41%). Short-term (few day) and long-term (decades) variability, as well as possible AGB contamination in the YSO catalogues, are also discussed.molecules become more complex by surface chemistry induced directly by high energy photons or by the thermal energy diffused over heated grain surface. Therefore, the ice composition is an

• 한국산학기술학회논문지
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• 제14권12호
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• pp.6373-6386
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• 2013

본 연구는 MBTI 성격유형과 심박변이도의 관계를 조사하기 위해 시도된 연구이다. 충청남도 C 시에 소재 한 N대학교 일개 응급구조학과 재학생들을 대상으로 학교 내에서 안정상태로 측정한 심박변이도와 병원 임상실습 중 2주째와 4주째에 측정한 심박변이도를 비교분석하였다. 자료수집기간은 2013년 6월 21일부터 7월 23일까지였으며, MBTI 성격유형에 따른 안정 및 실습기간의 심박변이도의 변화에서 네 가지 성격유형별 분포도에 따른 안정 및 실습기간의 HRV에서는 nHF와 SDNN에서 유의한 차를 보였다. 전체 지표별 선호 분포도에 따른 안정 및 실습기간의 심박변이도의 변화에서 nLF는 T-F, J-P 그룹, nHF에서는 T-F, J-P 그룹, SDNN에서는 S-N, mHR에서는 J-P 그룹에서 유의한 차이가 있었다.

• 동의신경정신과학회지
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• 제26권2호
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• pp.89-102
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• 2015

Objectives: To examine the medical effectiveness of meditation programs ($\alpha$ version) by psychological types. Methods: MBTI, which was created by Katharine Cook Briggs and Isabel Briggs Myers, was used as the Psychological Type test and to investigate psychological temperament and functions and psychological preferences. Heart rate variability was used to test the effectiveness of meditation by investigating time domains (mean HR, SDNN, PSI) and frequence domain parameters (TP, LF, HF, LF or HF norm, Ln (TP or VLF or LF or HF). Results: 1. The autonomic nervous system became active, and both time domains and frequency domains showed positive responses to meditation in heart rate variability tests, without distinction of Psychological Types. 2. In Psychological Types using sensing over intuition for perception, there were positive responses as well as an increase of the parasympathetic nervous system's activeness to meditation for heart rate variability tests, depending on psychological temperaments and psychological functions. 3. In heart rate variability tests by preferences, there was no difference. Extroversion and Introversion types, Sensing over Intuition Types, Thinking over Feeling Types, Judging over Perception Types had an increase of activeness of the parasympathetic nervous system. Therefore, meditation has a positive physical and psychological relaxing effect. Conclusions: A complex meditation program has a positive effect on overall meditation. Especially in the MBTI test, sensing was superior to intuition when people recognized objects. The Sensing, Thinking and Judging type was more advantageous than Intuition, Feeling and Perception, respectively. In the future, a well-designed control study is needed, to develop a suitable meditation for each personality type.

• 대기
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• 제24권1호
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• pp.89-99
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• 2014

Recently, several studies pointed out that there are distinct two types of El Ni$\tilde{n}$o events based on the spatial pattern of SST. Since the two types of El Ni$\tilde{n}$o have different impacts on global climate, it is quite important to identify the type to assess and predict the regional climate variability. So far, however, there are still many different definitions to identify the two types of El Ni$\tilde{n}$o from the different studies. In this study, we investigated a sensitivity of the impacts on climate variability over the Korean Peninsula corresponding to the definition of two-types of El Ni$\tilde{n}$o. After checking pre-existing definitions and other possible definition, it is suggested here that two different definitions exhibit relatively strong relationship between El Ni$\tilde{n}$o events and the Korean climate variables when two types of El Ni$\tilde{n}$o are separated. In addition to the Korean climate, the two types of El Ni$\tilde{n}$o show quite distinct global teleconnection patterns when the definitions are used.

• 한국지반공학회논문집
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• 제25권6호
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• pp.73-88
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• 2009

지반의 변동성은 많은 독립된 불확실성 요소로부터 발생하는 복잡한 요소이며, 지반의 변동성은 주로 내재적 변동성과 측정오차에 의해서 발생한다. 본 논문에서는 지반의 변동성을 평가하는 지표로 사용되는 변동계수를 송도지역의 지반정수 및 지층에 대하여 산정하였다. 지반정수의 변동성은 지층 및 흙의 종류에 영향을 받으므로 지층은 매립층과 퇴적층, 흙의 종류는 점토와 실트로 구분하여 각각의 변동계수를 산정하였다. 퇴적층과 점토의 변동계수가 매립층과 실트에 비하여 작은 것으로 분석되었다. 또한, 풍화가 많이 진행된 암반과 토사가 신선한 암반과 풍화암에 비하여 상대적으로 큰 변동계수를 보이는 것으로 나타났다. 본 논문에서 제시한 송도지역의 변동계수는 신뢰성해석의 자료로 사용될 수 있을 것으로 판단된다.

• 천문학회지
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• 제49권5호
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• pp.209-223
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• 2016

We present analyses of ~1250 variable sources identified in a 20 square degree field toward NGC 2784 by the KMTNet Supernova Program. We categorize the variable sources into three groups based on their B-band variability. The first group consists of 31 high variability sources with their B-band RMS variability greater than 0.3 magnitudes. The second group of medium variability contains 265 sources with RMS variability between 0.05 and 0.3 magnitudes. The remaining 951 sources belong to the third group of low variability with an RMS variability smaller than 0.05 magnitudes. Of the entire ~1250 sources, 4 clearly show periods of variability greater than 100 days, while the rest have periods shorter than ~51 days or no reliable periods. The majority of the sources show either rather irregular variability or short periods faster than 2 days. Most of the sources with reliable period determination between 2 and 51 days belong to the low-variability group, although a few belong to the medium-variability group. All the variable sources with periods longer than 35 days appear to be very red with B - V > 1.5 and V - I > 2.1 magnitudes. We classify candidates of 51 Cepheids, 17 semi-regular variables, 3 Mira types, 2 RV(B) Tauri stars, 26 eclipsing binary systems and 1 active galactic nucleus. The majority of long-term variables in our sample belong to either Mira or semi-regular types, indicating that long-term variability may be more prominent in post-main sequence phases of late-type stars. The depth of the eclipsing dips of the 26 candidates for eclipsing binaries is equivalent to ~0.61 as the average relative size of the two stars in the binary system. Our results illustrate the power of the KMTNet Supernova Program for future studies of variable objects.