• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.232-237
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• 2021

Pre-Corona cultural content was largely formed face to face. For example, the service was great while visiting tourist attractions, visiting performances to see K-Pop, or visiting lectures to learn K-Beauty. However, after the coronation, the virtual world-centered Metaverse began to take the spotlight as non-face-to-face services changed. IT and cultural contents have been combined and developed into various digital services. In that sense, Metaverse, which breaks the boundaries between real-world space and virtual space, has the potential to escape from physical time and space constraints. However, Korea still lacks a Metaverse platform for cultural content. In particular, it is necessary to match each other's necessary services by providing Metaverse -oriented cultural contents that users want, including experienced cultural contents such as K-pop and K-beauty, away from cultural contents that are developed around history museums. Therefore, in this paper, we would like to propose a Metaverse-based cultural content matching platform where users can experience cultural content directly or indirectly.

• Earthquakes and Structures
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• 제16권1호
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• pp.29-39
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• 2019

A three-step screening process is presented in this article for selection of consistent earthquake records in which number of suitable ground motions is quickly screened and reduced to a handful number. Records that remain at the end of this screening process considerably reduce the dispersion of structural responses. Then, an effective method is presented for spectral matching and modification of the selected records. Dispersion of structural responses is explored using different statistical measures for each scaling procedure. It is shown that the Uniform Design Method, presented in this study for scaling of earthquake records, results in most cases in the least dispersion measure.

• 천문학회보
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• 제44권1호
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• pp.40.1-40.1
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• 2019

We utilize times since infall of cluster galaxies obtained from Yonsei Zoom-in Cluster Simulation (YZiCS), the cosmological hydrodynamic N-body simulations, and star formation rates from the SDSS data release 10 to study how quickly late-type galaxies are quenched in the cluster environments. In particular, we confirm that the distributions of both simulated and observed galaxies in phase-space diagrams are comparable and that each location of phase-space can provide the information of times since infall and star formation rates of cluster galaxies. Then, by limiting the location of phase-space of simulated and observed galaxies, we associate their star formation rates at z ~ 0.08 with times since infall using an abundance matching technique that employs the 10 quantiles of each probability distribution. Using a flexible quenching model covering different quenching scenarios, we find the star formation history of satellite galaxies that best reproduces the obtained relationship between time since infall and star formation rate at z ~ 0.08. Based on the derived star formation history, we constrain the quenching timescale (2 - 7 Gyr) with a clear stellar mass trend and confirm that the refined model is consistent with the "delayed-then-rapid" quenching scenario: the constant delayed phase as ~ 2.3 Gyr and the quenching efficiencies (i.e., e-folding timescale) outside and inside clusters as ~ 2 - 4 Gyr (${\propto}M_*^{-1}$) and 0.5 - 1.5 Gyr (${\propto}M_*^{-2}$), Finally, we suggest: (i) ram-pressure is the main driver of quenching of satellite galaxies for the local Universe, (ii) the quenching trend on stellar mass at z > 0.5 indicates other quenching mechanisms as the main driver.

• Earthquakes and Structures
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• 제16권5호
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• pp.563-573
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• 2019

When generating spectrum-compatible artificial ground motion in engineering practices, the effect of the variation in fitting parameters on the distribution of the peak ground displacement (PGD) has not yet drawn enough attention. In this study, a method for simulating ground motion matching for multiple targets is developed. In this method, a frequency-dependent amplitude envelope function with statistical parameters is introduced to simulate the nonstationarity of the frequency in earthquake ground motion. Then, several groups of time-history acceleration with different temporal and spectral nonstationarities were generated to analyze the effect of nonstationary parameter variations on the distribution of PGD. The following conclusions are drawn from the results: (1) In the simulation of spectrum-compatible artificial ground motion, if the acceleration time-history is generated with random initial phases, the corresponding PGD distribution is quite discrete and an uncertain number of PGD values lower than the limit value are observed. Nevertheless, the mean values of PGD always meet the requirement in every group. (2) If the nonstationary frequencies of the ground motion are taken into account when fitting the target spectrum, the corresponding PGD values will increase. A correlation analysis shows that the change in the mean and the dispersion values, from before the frequencies are controlled to after, correlates with the modal parameters of the predominant frequencies. (3) Extending the maximum period of the target spectrum will increase the corresponding PGD value and, simultaneously, decrease the PGD dispersion. Finally, in order to control the PGD effectively, the ground motion simulation method suggested in this study was revised to target a specified PGD. This novel method can generate ground motion that satisfies not only the required precision of the target spectrum, peak ground acceleration (PGA), and nonstationarity characteristics of the ground motion but also meets the required limit of the PGD, improving engineering practices.

• KDI Journal of Economic Policy
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• 제39권1호
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• pp.1-18
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• 2017

This paper empirically studies the effect of public procurement on small and medium-sized enterprises (SMEs) in the Republic of Korea using firm-level data. Public procurement, the purchase of goods and services from private firms by the public sector, is regarded as an important policy measure for providing support to firms, particularly SMEs. This study uses establishment-level panel data of the mining and manufacturing sectors from the Korean National Bureau of Statistics (Statistics Korea) and procurement history from the Korean Public Procurement Service to empirically estimate the effects of public procurement on firms' productivity (total factor productivity) and survivability. Using a propensity score matching estimation method, we find that participating firms showed higher productivity than non-participating ones in the control group only for the year of participation, that is, 2009. After two years, in 2011, they exhibited significantly lower productivity. In contrast, establishments that participated in public procurement for SMEs in 2009 were more likely to survive than those that did not do so in 2011. These results can be interpreted as the negative consequences of government intervention. The market's efficiency enhancement is hindered if underserving companies survive owing to government intervention but fail to improve efficiency.

• Nutritional Sciences
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• 제3권2호
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• pp.77-82
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• 2000

We carried out a case-control study to investigate protective effect of lactating against breast cancer in Korea. Cases (n=108) were the newly histologically identified breast cancer between December 1997 and August 1999. Hospital-based controls were selected by frequency matching method with age ($\pm$4 age) and menopausal status from the patients at the same hospital in the plastic surgery, general surgery and opthalmology department. Interviews included information on general characteristics of subjects, disease history, family history of breast cancer, vitamin supplementation, alcohol intake, food intake, and reproductive factors as well as lactation history. Odds ratio (OR) and 95% Confidence Intervals (CI) were calculated by using unconditional logistic regression. Age distribution of case control subjects were similar. Late menarche age $\geq$ 17 in premenopausal women was related to the lower risk of breast cancer OR = 0.41, 95% CI = 0.28-0.91. Family history of breast cancer was related to the higher risk of breast cancer only in premenopausal women (OR = 2.07, 95% CI = 1.35-2.71). Higher body mass index mass index (> 30) were associated with higher risk of breast cancer in postmenopausal women. For premenopausal women, women who had lactated $\geq$ 12 months to the first child had a significantly lower risk (OR = 0.53, 95% CI = 0.24-0.97) than the women had no breast feeding experience. However, results from postmenopausal women did not show an association with decreased breast cancer risk. These findings suggest that lactation may be a protective factor of breast cancer in Korean women.

• 한국의사학회지
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• 제22권1호
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• pp.31-45
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• 2009

Eui Bang Shin Gam("醫方新鑑") is a classic on oriental medicines written by Shin Oh (新塢) Han Byung Lyun (韓秉璉) in 1913. It was written under the base of the writer's own experience as well as in the light of 36 other classics on oriental medicines such as Dong Eui Bo Gam ("東醫寶監"), Eui Hak Yip Mun ("醫學入門"), and Kyung Ak Jeon Seo ("景岳全書"). In an attempt to avoid difficult theories and list only the essential informations and formulas for clinical purposes, it attained its own characteristics of not only reorganizing Dong Eui Bo Gam in a pragmatic way but also explaining diseases classified in western medicines in oriental medicines' point of view as well as suggesting medicine formulas regarding such explanations. As a result, it is a complete and efficient medical classic through which one can gain knowledge in both classic oriental medicines and combination of western and oriental medicines. Its special features are making a separate chapter for cholera and Lao Zhai (勞瘵), which is also a contagious disease, and trying in the chapter to explain the diseases in words of oriental medicines; listing details of nine major epidemic and matching them with the diseases known in oriental medicines; and recording a case of enforcing sterilization and preventive injection against contagious diseases. The basic medical theory in Eui Bang Shin Gam are the yin-yang theory, the thesis of fire and water, the thesis of the exterior and the interior, Yun Qi Lun (運氣論), and four institutions of human body. In explaining the basic theories, the writer emphasized strengthening the yang of the body, under the influence of the thoughts of Zhang Ga Bin (張介賓). Since he put the importance of diagnosis first, the first chapter is about diagnosis. There are five different ways of diagnosing a patient mentioned in the book, and acupuncture, pulse, and medicines was considered crucial.

• 한국측량학회지
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• 제32권4_1호
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• pp.311-318
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• 2014

건물 데이터는 지도 데이터베이스에서 차지하는 비중이 높고 객체 수도 많을 뿐만 아니라 형상정보 및 속성정보가 빠르게 변화하기 때문에, 최신 정보에 근거한 효율적인 갱신 작업은 필수적이다. 본 연구에서는 갱신 참조 건물데이터와 갱신 대상 건물 데이터의 중첩분석을 통해 갱신이 필요한 객체만을 탐색하여 갱신을 수행하고자 한다. 즉, 건물의 중첩 면적비를 이용하여 매칭 후보쌍을 탐색한 후, 속성정보 비교를 통해 갱신 케이스 분류 조건식을 정의하였으며, 이때 도형정보 갱신 케이스는 총 8가지, 속성정보 갱신 케이스는 총 4가지로 각각 분류하였다. 또한 갱신정보에 대한 갱신 이력 데이터가 자동으로 생성되도록 하여 두 가지 종류의 갱신 케이스 정보를 저장하도록 구성하였다. 갱신 대상 데이터는 수치지도 1:5,000 건물외곽선 레이어로 하였고, 갱신 참조 데이터는 도로명주소전자지도건물 레이어로 하였으며, 서울시 관악구 지역을 대상지역으로 선정하였다. 본 연구의 매칭기반 갱신기법을 적용한 결과, 전체 건물데이터 중, 82.1%의 건물이 도형정보를 수정하였고, 34.5% 건물이 속성정보를 수정하였다.

• 한국게임학회 논문지
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• 제21권6호
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• pp.31-40
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• 2021

바둑은 2,500년 이상의 역사를 지녔고, 바둑에서의 사활문제는 컴퓨터 바둑을 구축 시에 반드시 해결해야 되는 기본 문제영역이 된다. 본 논문에서는 사활문제와 직결되는 3, 4, 5, 6궁에 대한 원형 안형의 개수 확인과 4-튜플 형식으로 표현된 원형 안형을 분류하고자 했다. 실험은 몬테카를로 방법과 점 패턴 매칭에 의해 수행되었다. 실험 결과에 따르면 원형 안형의 개수는 3궁 2개, 4궁 5개, 5궁 12개, 6궁 35개가 된다. 아울러 4-튜플 형식으로 된 원형 안형을 분류하면 3궁 1가지, 4궁 3가지, 5궁 4가지, 6궁 8가지로 분류된다.

• 한국수학사학회지
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• 제23권3호
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• pp.45-56
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• 2010

순차식 연산은 겐첸이 자연연역을 1934년 대칭적 버전으로 재구성한 것으로서, 여기에서 그는 '주정리' 를 소개한다. 이 논문에서 우리는 절단의 유용성에도 불구하고 증명이론에서 왜 절단정리가 이토록 중요한 위상을 차지하는지 검토할 것이다. 이어서 커리-하우어드 대응의 역동적 측면, 즉 절단 제거와 단순히 유형화된 람다-연산에서 ${\beta}$-환원의 대응이 연구될 것이다. 이러한 대응의 중요성은 프로그램의 세계와 수학 증명의 세계를 마주보게 함으로써 프로그램의 정확성을 보증해준다는 데에 있다.