• 한국환경복원기술학회지
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• 제14권2호
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• pp.1-10
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• 2011

Six pine trees (Pinus densiflora S. et Z.) at the Euilimji Lake Park in Jecheon were collected to investigate tree ages, growth decline pattern and the years of death. Tree-ring measurement was carried out using the Lintab with a resolution of 0.01mm. Tree age were 80-176 years. Cross-dating between the tree-ring series of each tree and the local chronology from Worak Mountain resulted that four and two trees died in 1998 and 1999, respectively. Three dead trees had only formed earlywood in the outermost tree ring and the others had incomplete latewood. Therefore, it was proven that the former trees died between spring and early summer, whereas the later ones died during late summer and/or autumn. The simultaneous deaths of trees suggest the insect damage and/or drought may be the crucial reason of the death, but frequent reaction woods, which were formed by leaning stem, and scars formed by physical damage may also contribute to the death.

• Journal of Ecology and Environment
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• 제37권2호
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• pp.105-111
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• 2014

To elucidate whether small diameter at breast height correlates with tree death in an overcrowded tree population, we analyzed self-thinning occurring over the course of 37 years in naturally established Pinus densiflora populations in Sugadaira, central Japan. As trees grew, their diameters at breast height increased and the number of trees consequently decreased. Spatial distribution, which was initially clumped, changed accordingly, first becoming random and finally uniform. We calculated the "available area" of individual trees to elucidate the contribution of this parameter to tree mortality. Small diameter at breast height was strongly correlated with tree death, with a slight correlation observed between tree death and small available area of individual trees.

• Journal of the Korean Wood Science and Technology
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• 제52권4호
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• pp.319-330
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• 2024

The present study aimed to investigate the death years of conifers to verify the time difference between landslide occurrence in 2011 and tree mortality near Chibanmok and Jangteomok shelters in the Jirisan National Park. Furthermore, abrupt growth reduction was also investigated to verify the living conditions when they were living. For the study, tree-ring analysis was conducted by selecting 14 living Abies koreana near the landslide area and 7 dead ones in the landslide area in the Chibanmok site, and 13 living conifers (7 Picea jezoensis, 5 A. koreana, and 1 Pinus koraiensis) near landslide area and 4 dead ones (2 P. jezoensis and 2 A. koreana) in landslide area in the Jangteomok site. Using the tree-ring samples from living A. koreana 137-year long chronology (1885-2021) was established for the Chibanmok site and 364- and 65-year long P. jezoensis (1658-2021) and A. koreana (1957-2021) chronologies was built for the Jangteomok site. Through the synchronization test between the tree-ring time series from dead conifers and the corresponding chronologies, it was verified that the death of conifers in the landslide areas occurred after 2011, when the landslide happened, except for only one tree. It was further verified through the abrupt growth reduction test that the growth condition of dead conifers before the landslide in 2011 was satisfactory.

• 한국건설관리학회논문집
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• 제22권5호
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• pp.55-65
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• 2021

건설업은 타 산업에 비해 높은 사망사고율을 보이고 있으며, 최근 사망사고에 대한 기업의 법적 책임이 강화되고 있다. 이는 건설사에게 큰 부담이 되고 있으며, 건설 사망사고에 대한 선제적 예측과 관리의 필요성을 증대시키고 있다. 본 연구의 목적은 의사결정나무를 활용하여 건축공사에서 발생할 수 있는 사망사고를 사전에 예측할 수 있는 모델을 개발하는데 있다. 본 연구에서 의미하는 사망사고 예측모델이란 건축공사의 조건에 따라 공종별로 발생할 수 있는 사망사고의 가능성(확률)을 예측하는 모델을 의미한다. 예측모델의 활용을 통한 사망사고에 대한 사전 예측과 선제적 대응은 법적 처벌을 예방하고 건축공사의 성공적인 수행이라는 측면에서 중요한 의의를 지닌다.

• 한국환경복원기술학회지
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• 제22권3호
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• pp.1-14
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• 2019

With a view to developing a database of death years of Korean firs (Abies koreana) at Yeongsil in Mt. Halla and investigating their abrupt inter-annual growth reduction tree-ring analysis was employed. To this end, 10 living trees (YSL) were selected to establish a master chronology and 20 dead trees were used to date their dead years. To investigate the difference in death years by death types, 10 trees, which remained standing (YSSD) out of the 20 dead trees were selected. The rest 10 dead trees were already fallen (YSFD). Two increment cores per tree at breast height were extracted in contour direction using an increment borer. A 106-year master chronology (1911-2016) was successfully established from the 10 YSLs. Through cross-dating between individual YSSD time series and the master chronology, it was verified that 1 YSSD was dead in summer 1978, 1 YSSD between autumn 1999 and spring 2000, 2 YSSDs in summer 2007, 1 YSSD in summer 2010, 1 YSSD in summer 2012, and 1 YSSD in summer 2013. The youngest tree rings of 2 YSSDs having no bark were in 1977 and 2002. For the YSFDs, it was verified that 1 YSFD was dead between autumn 1997 and spring 1998, 1 YSFD between autumn 2001 and spring 2002, 2 YSFDs between autumn 2009 and spring 2010, 1 YSFD in summer 2010, and 2 YSFDs between autumn 2012 and spring 2013, while the youngest tree rings of 2 YSFDs having no bark were in 1989 and 2004. To note, the death years of two trees, one from each death type (YSSD and YSFD), could not be verified due to poor cross-dating with the master chronology. The inter-annual growth reductions of YSSD and YSFD occurred more frequently and intensively than YSL. Typically, the YSFD showed the most frequent and intensive inter-annual growth reduction. On comparing the inter-annual growth reductions with the corresponding records of typhoons however we could not find any reliable relationship. Finally, from prior reports and results of the current study it can be concluded that the death and abrupt growth reduction of korean fir at Yeongsil in Mt. Halla are not caused by only a certain environmental factor but various factors.

• 영어어문교육
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• 제12권4호
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• pp.277-290
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• 2006

This study is to find out the meaning of the death in Donne's "Holy Sonnets" and divine poems. Death issue is the important theme and is used frequently in his poems. He expresses an assertion of faith about the defeat of death and wishes to gain new birth and eternal life through death. Ironically death must be died for rebirth and an inevitable death. Death is another way to get new life and return to Christ. Many readers think that "Hymn to God my god, in my sickness" is Donne's most distinguished achievement in his divine poems. The poem shows that death must be accepted willingly because it is only through death that man can reach heavenly bliss and gain new life. He develops an antithetic parallel between two hills and two trees. Paradise and Adam's tree which brought death into the world are related analogically to Calvary and the Cross, which brought resurrection and eternal life. Death and resurrection are shown to be conjoined in the poem. To sum up, Donne tried to pursuit death for rebirth and modeled after Christ's death and Resurrection.

• 한국산학기술학회논문지
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• 제19권1호
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• pp.300-310
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• 2018

본 연구는 대학생들이 죽음학 강좌 수강 이전과 이후 웰다잉 인식과 결정이 어떻게 변화되었는가를 비교 연구하고자 한다. 대전광역시 소재 일개 대학교에서 죽음학 관련 교양강좌를 2016년 8월부터 12월까지 15주 동안 수강한 대학생 교육 전 93명, 교육 후 117명 대상으로 연구 참여 희망자에 한해 설문조사를 실시하였다. 설문구성은 일반적인 특성은 성별, 연령, 학년, 전공, 결혼상태, 종교, 가족 동거여부, 건강상태 8항목이었다. 죽음의 인식 측면에 관한 4항목, 죽음의 수용 측면 5항목, 죽음의 결정 측면 7항목, 죽음 교육의 관심도와 중요도 12항목을 리커트 척도로 구성하였다. 통계 검정법으로는 카이제곱검정, 독립표본 t-검정, 의사결정나무 분석을 실시하였다. 연구결과를 의사결정나무 토대로 종합해보면, 죽음 준비 시기가 죽음에 직면한 시기(암환자, 말기환자 등)와 노인(65세 이상)에서 교육 전이 66.7%로 나타났으나, 교육 후에는 성인과 중 고등학교, 초등학교 이하, 대학교, 대학원에서 교육 후가 65.3%로 나타났으며 이는 유의한 차이를 보였다. 따라서 죽음교육의 효과성과 죽음교육의 시기와 내용 등을 어떻게 구체화 시킬 것인가에 대한 방향 제시를 할 수 있을 것으로 기대되며, 초 중 고등학교, 대학교에서의 죽음교육 실시에 대한 부정적인 시각과 우려를 해소하고 죽음 교육이 학생들의 삶에 태도 변화에 긍정적인 영향을 미칠 것으로 사료된다.

• 디지털융복합연구
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• 제17권9호
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• pp.79-88
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• 2019

본 연구에서는 데이터 마이닝 기법을 활용하여 항공기 사고와 준사고로 인한 사망 발생 요인들과 패턴들을 분석하고자 한다. 이를 위해, 항공기 사고와 준사고 데이터를 보유하고 있는 미국연방교통안전위원회(NTSB)와 미국연방항공청(FAA)의 데이터를 사용하였다. 다음으로 의사결정나무 알고리즘을 사용하여 항공기 사고 및 준사고에 따른 사망여부 예측모형들을 구축하였고 이를 토대로 사망 발생에 영향을 주는 주요 요인들과 패턴들을 도출하였다. NTSB 데이터의 경우 항공기가 완파되거나 고기동 또는 고위험 임무를 수행할 때 주로 사망이 발생하는 것을 알 수 있었다. FAA 데이터의 경우 항공기가 일부 파괴된 경우 조종사의 숙련도가 저조하거나 미인가 조종사의 경우 사망이 발생하였으며, 고공낙하점프와 지상운용단계에서 발생되는 다양한 사망관련 패턴들도 발견되었다. 또한 도출된 패턴들을 활용하여 사망 사고 예방을 위한 실용적인 방안들을 제시한 점에서 연구의 의의를 찾을 수 있다.

• The Korean Journal of Ecology
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• 제15권4호
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• pp.395-410
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• 1992

Disturbance regime and tree regeneration were studied in kwangnung natural forest, an old-growth deciduous hardwood forest located in central korea. This forest is dominated by carpinus laxiflora, c.erosa, and quercus species. The area occupied by canopy gaps was 4.6% of the total forested area, and the mean size of canopy gaps was 92 $m^2$ with the maximum being 524 $m^2$. More than half of the gaps were less than four years old, and 3/4 of the gaps were created by death of only or two canopy trees, indicating the dominance of small-sized gaps in kwangnung forest. about half of the gap-makers were c. laxiflora, and another one third were quercus species. In contrast, the most frequent relacers were c. laxiflora while quercus species filled only 5% of the gaps, suggesting a future shift in tree species composition under the current disturbance regime. tree regeration was more conspicuous even in small gaps than non-gaps regardless of shade-tolerance of tree species, indicating the importance of gaps in tree regeneration.

• Environmental Engineering Research
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• 제23권4호
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• pp.430-441
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• 2018

The adverse health impact of air pollution is becoming more serious. The purpose of this study is twofold: One is to analyze the effect of air pollution and temperatures on human health by analyzing the number of deaths from cardiovascular disease in Seoul, Korea; the other is to determine what impact the location of a monitoring site has on the results of a health study. For this latter purpose, air pollution and temperature monitors are sited at three locations termed green, public, and residential. Then, a decision tree model is used to analyze factors linked with deaths occurring at each monitoring site. The results show that the environmental temperatures before death and the $PM_{2.5}$ concentrations on the day of death are highly linked with the number of deaths regardless of the monitoring location. However, results are most accurate with residential data. The results of this study can be used as base data for a similar analysis and ultimately, as a guide to minimize the health impact of air pollution.