• 유통과학연구
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• 제14권1호
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• pp.93-102
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• 2016

Purpose - The purpose of paper is studying the static and dynamic side for long-term memory storage properties, and increase the explanatory power regarding the long-term memory process by looking at the long-term storage attributes, Korea Composite Stock Price Index. The reason for the use of GPH statistic is to derive the modified statistic Korea's stock market, and to research a process of long-term memory. Research design, data, and methodology - Level shifts were subjected to be an empirical analysis by applying the GPH method. It has been modified by taking into account the daily log return of the Korea Composite Stock Price Index a. The Data, used for the stock market to analyze whether deciding the action by the long-term memory process, yield daily stock price index of the Korea Composite Stock Price Index and the rate of return a log. The studies were proceeded with long-term memory and long-term semiparametric method in deriving the long-term memory estimators. Chapter 2 examines the leading research, and Chapter 3 describes the long-term memory processes and estimation methods. GPH statistics induced modifications of statistics and discussed Whittle statistic. Chapter 4 used Korea Composite Stock Price Index to estimate the long-term memory process parameters. Chapter 6 presents the conclusions and implications. Results - If the price of the time series is generated by the abnormal process, it may be located in long-term memory by a time series. However, test results by price fixed GPH method is not followed by long-term memory process or fractional differential process. In the case of the time-series level shift, the present test method for a long-term memory processes has a considerable amount of bias, and there exists a structural change in the stock distribution market. This structural change has implications in level shift. Stratum level shift assays are not considered as shifted strata. They exist distinctly in the stock secondary market as bias, and are presented in the test statistic of non-long-term memory process. It also generates an error as a long-term memory that could lead to false results. Conclusions - Changes in long-term memory characteristics associated with level shift present the following two suggestions. One, if any impact outside is flowed for a long period of time, we can know that the long-term memory processes have characteristic of the average return gradually. When the investor makes an investment, the same reasoning applies to him in the light of the characteristics of the long-term memory. It is suggested that when investors make decisions on investment, it is necessary to consider the characters of the long-term storage in reference with causing investors to increase the uncertainty and potential. The other one is the thing which must be considered variously according to time-series. The research for price-earnings ratio and investment risk should be composed of the long-term memory characters, and it would have more predictability.

• 한국습지학회지
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• 제15권4호
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• pp.493-500
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• 2013

강화 남부 갯벌의 장기적인 퇴적환경 변화를 파악하기 위하여 1997년과 2011년 여름철 표층 퇴적물의 분포와 1998년 4월과 2013년 3월의 갯벌 고도를 비교하였다. 표층퇴적물은 1997년에 동부의 펄, 서부의 모래 펄 퇴적물이 우세하였으나, 2011년에는 동부의 선두리와 동검도 갯벌은 펄과 모래 펄, 중부의 동막리 갯벌은 모래 펄, 그리고 서부의 여차리와 장화리 갯벌은 모래와 펄 모래 퇴적물이 우세하게 분포하였다. 지난 14년 동안 펄 퇴적물 면적은 감소하였으나, 모래와 펄 혼합 퇴적물의 면적은 동쪽으로 확장되었다. 갯벌의 장기적인 지형 변화는 지난 15년 동안 동막리와 여차리 갯벌은 퇴적, 장화리 갯벌은 침식된 것으로 나타났다. 이러한 변화들은 1990년대 이후 강화 남부 갯벌 주변에 여러 종류의 인공구조물건설에 의하여 지역적인 수리적 변화가 영향을 주었을 것이다.

• Smart Structures and Systems
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• 제15권2호
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• pp.395-408
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• 2015

This study aims to propose a Bayesian approach to consider changes in temperature and vehicle weight as environmental and operational factors for vibration-based long-term bridge health monitoring. The Bayesian approach consists of three steps: step 1 is to identify damage-sensitive features from coefficients of the auto-regressive model utilizing bridge accelerations; step 2 is to perform a regression analysis of the damage-sensitive features to consider environmental and operational changes by means of the Bayesian regression; and step 3 is to make a decision on the bridge health condition based on residuals, differences between the observed and predicted damage-sensitive features, utilizing 95% confidence interval and the Bayesian hypothesis testing. Feasibility of the proposed approach is examined utilizing monitoring data on an in-service bridge recorded over a one-year period. Observations through the study demonstrated that the Bayesian regression considering environmental and operational changes led to more accurate results than that without considering environmental and operational changes. The Bayesian hypothesis testing utilizing data from the healthy bridge, the damage probability of the bridge was judged as no damage.

• Asian review of World Histories
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• 제3권2호
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• pp.171-200
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• 2015

At its simplest, this essay provides a narrative of migration in Asia since the arrival of Homo sapiens some 70,000 years ago. More fully, it presents the case for conducting long-term, world-historical interpretation for Asia with attention to multiple perspectives, which has become increasingly central to global historical analysis. Following an introductory articulation of the benefits of long-term interpretation, the second section presents a balance of three perspectives-empire, exchange, and migration-as frameworks for interpreting the Asian past. The third section presents further detail on migration in long-term Asian history. The concluding section identifies four changes in patterns of migration during the past two centuries and emphasizes the underlying importance of cross-community migration in long-term human biological and social evolution.

• 한국연초학회지
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• 제23권1호
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• pp.31-39
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• 2001

This study was carried out to investigate the changes of physical and chemical properties and the usability of long-term stored leaf tobacco. The physical chemical properties of the flue-cured and burley leaves produced in 1993, processed in 1994 were analysed from Nov. 1996 to Nov. 1999. The pH and moisture content in leaf decreased slowly until 4 years’storage after processing, while those of leaf changed little thereafter. However, total sugar content continuously decreased until 5 years after processing. The filling capacity increased and shatter resistance index decreased in long-term stored leaf. The sensory test, cilia stasis and the chemical components of cigarette smoke had no significant differences between short and long-term stored leaves. When the processed leaves were stored till 5 years after processing, there were no deteriorative effects on quality and usability of leaf tobacco. Therefore, it is considered that the processed leaf may be stored for 5 years or more under the inevitable situation.

• 한국환경과학회지
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• 제3권1호
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• pp.11-16
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• 1994

Generally, it is difficult to predict water quality in a tidal river, because tidal flows make the transport phenomena more complicated. The purpose of this study is to clarify long-term mass transport in a tidal river through suggestion of simulation model. A simulation model based on a Lagrangian coordinate system, which has the advantage reducing numerical dispersion, was used to calculate changes in concentration of chlorides. Several field surveys were conducted to verify calculated results. Concludingly, long-term behavior of mas transport in a tidal river can be represented using the model.

• 천문학회지
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• 제29권spc1호
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• pp.227-228
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• 1996

The long-term light curves of the novalikes TT Ari, KR Aur, AM Her and MV Lyr, were compiled and analysed for solar-like cyclical behaviour. The frequency analysis showed long-term cyclical modulations of the brightness of the stars, which can be ascribed to changes of the radii of the late type secondaries in order of ${\Delta}R/R{\simeq} 10^{-4}-10^{-5}$.

• 한국콘텐츠학회논문지
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• 제15권7호
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• pp.228-243
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• 2015

본 연구에서는 노동조합 조합원인 장기해고노동자들이 해고와 이후 실업기간을 어떻게 경험하는지 그 변화과정을 현상학적 방법으로 분석하였다. 연구대상자는 평균해고 기간이 8년 4개월인 남성 해고노동자로 5명을 심층 면담하였다. 해고 당시의 심리적 경험, 해고 이후 지속적인 심리적 또는 신체적 변화, 현재 상태, 해고기간 동안의 대처방법 등을 반구조화 질문지에 근거하여 심층 면담을 진행하여 자료를 수집하였다. 이를 분석한 결과 21개의 하위 주제와 이를 포괄하는 5개의 상위주제를 구성하였다. 중요상위주제는 '해고 당시와 이후의 감정과 인식', '해고가 장기화되면서 생기는 증상과 변화', '장기화된 현재의 상태', '사회적 인식에 대한 양상', '해고에 대한 대처' 이었다. 상위주제와 하위범주에 대하여 기술하고 이와 관련된 장기해고노동자의 경험을 구체적으로 기술하였다. 마지막으로 장기해고노동자의 변화 및 경험을 선행연구를 바탕으로 논의하였다.

• 한국산림과학회지
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• 제109권4호
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• pp.544-552
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• 2020

본 연구는 국립산림치유원에서 2019년 진행된 장기체류 산림치유프로그램 「숲 속 힐링스테이」에 참가한 49명을 대상으로, 참여 전·후 설문조사 및 혈압, 체성분, HRV 등 신체변화를 측정하여 프로그램의 효과성을 분석했다. 연구결과, 장기체류 산림치유프로그램 참여 후에 참여자의 부정감정이 통계적으로 유의하게 감소하였고, 자율신경 균형도는 통계적으로 유의하게 증진되어 긍정적인 효과를 확인할 수 있었다. 병력 유무에 따른 체력측정 변화를 살펴본 결과 악력 및 제자리높이뛰기 증가 정도가 통계적으로 유의한 차이가 있었으며, 병력이 있는 사람들이 병력이 없는 사람들에 비해 증진 효과가 더 높게 나타났다. 본 연구에서는 단기형 프로그램 효과검증에서 벗어나 6박7일 장기체류 형태의 산림치유 효과성을 확인한 것에 그 의의가 있다.

• 보건행정학회지
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• 제32권4호
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• pp.389-399
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• 2022

Background: This study aimed to analyze changes in medical utilization and cost before and after long-term care (LTC) implementation. Methods: We used the National Health Information Database from National Health Insurance Service. The participants were selected who had a new LTC grade (grade 1-5) for 2015. Medical utilization was analyzed before and after LTC implementation. Segmented regression analysis of interrupted time series was conducted to evaluate the overall effect of the LTC implementation on medical costs. Results: The total number of participants was 41,726. A major reason for hospitalization in grade 1 was cerebrovascular diseases, and dementia was the top priority in grade 5. The proportion of hospitalization in grade 1 increased sharply before LTC implementation and then decreased. In grade 5, it increased before LTC implementation, but there was no significant difference after LTC implementation. As for medical cost, in grades 1 to 4, the total cost increased sharply before the LTC implementation, but thereafter, changes in level and trend tended to decrease statistically, and for grade 5, immediately after LTC implementation, the level change was decreasing, but thereafter, the trend change was increasing. Conclusion: Long-term care grades showed different medical utilization and cost changes. Long-term care beneficiaries would improve their quality of life by adequately resolving their medical needs by their grades.