• Title/Summary/Keyword: Tree death

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Examination of Death Years and Causes by the Analysis of Growth Decline in Tree Rings of Pinus densiflora from the Euilimji Lake Park in Jecheon, Korea (제천 의림지 소나무 연륜생장 쇠퇴도 분석을 통한 고사 연도 및 원인규명 연구)

  • Seo, Jeong-Wook;Park, Won-Kyu
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.14 no.2
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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.

Relation of mortality to DBH and available area in naturally germinated Pinus densiflora populations

  • Kato, Jun;Degawa, Yousuke
    • Journal of Ecology and Environment
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    • v.37 no.2
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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.

Investigating into the Death Years of Evergreen Conifers in Landslide Areas of Jirisan National Park and the Abrupt Growth Reduction During Their Living

  • Jun-Hui PARK;En-Bi CHOI;Yo-Jung KIM;Ju-Ung YUN;Jin-Won KIM;Hyeon-Ho MYEONG;Jeong-Wook SEO
    • Journal of the Korean Wood Science and Technology
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    • v.52 no.4
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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.

Predictive Analytics Model for Death Accidents in Building Projects by Trade - Based on Decision Tree- (PA기법을 이용한 건축공사 공종별 사망사고 예측모델 개발에 관한 연구 - 의사결정나무를 중심으로 -)

  • Choi, Jeong Won;Kim, Han Soo
    • Korean Journal of Construction Engineering and Management
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    • v.22 no.5
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    • pp.55-65
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    • 2021
  • Compared with other industries, construction industry shows a higher rate of death accidents and recently companies' legal responsibilities are to be increasingly enforced. The trend causes tremendous concerns for construction firms and increases the importance of forecasting and pro-actively managing death accidents in construction fields. The objective of the study is to develop a predictive analytics model for forecasting death accidents in building projects based on a decision tree technique, which enables to forecast the probabilities of death accidents by trade. The use of the model helps to decrease risks of legal punishments and to assist the safe execution of building projects by forecasting and pro-actively managing death accidents.

Investigation of Death Years and Inter-annual Growth Reduction of Korean Firs (Abies Koreana) at Yeongsil in Mt. Halla (한라산 영실지역 구상나무 고사연도와 시계열적 생육쇠퇴도 조사)

  • Seo, Jeong-Woo;Kim, Yo-Jung;Choi, En-Bi;Park, Jun-Hui;Kim, Jae-Hoon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.3
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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.

John Donne's "Holy Sonnets": The song of rebirth (존 던의 "거룩한 쏘넷": 부활의 노래)

  • Jung, Kyung-Mi
    • English Language & Literature Teaching
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    • v.12 no.4
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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.

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A Study on the Well-Dying Recognition and Decision of Death before and after Education Among University Students (대학생들의 죽음 교육 전과 후의 웰다잉 인식과 결정에 관한 연구)

  • Song, Hyeon-Dong;Ahn, Sang-Yoon;Kim, Yong-Ha;Hwang, Hye-Jeong;Lee, Seo-Hui;Kim, Kwang-Hwan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.300-310
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    • 2018
  • The purpose of this study is to compare the change of Well-Dying awareness and decision of university student before and after taking the course of death study. A questionnaire survey was conducted for university students 93 before education, 117 after education who participated in the Death Studies related lectures at Daejeon Metropolitan City for 15 weeks from August to December 2016. The general characteristics of survey are gender, age. grade, major, marriage condition, religion, family member living together and health status. Four items on the perception aspect of death, five items on the aspect of acceptance of death, seven items of death decision and twelve items for death education's interest and importance were configured as a reference scale. The statistical method carried out the chi-square test, the independent sample t-test, and the decision tree analysis. Based on the decision tree, At the time of preparation for death(cancer patient, terminal patient, etc.) and the elderly(65 years old or older), the education transition rate was 66.7%. But After education, 65.3% of the respondents were in adult, middle and high school, under elementary school, university, and graduate school, which showed a significant difference. Therefore we are looking for death education's effectiveness and setting directions for education's period and contents. the negative viewpoints and worries about the implementation of death education at elementary, middle and high schools and universities are resolved and the death education will positively affect the change of attitude of students.

Analysis of the Factors and Patterns Associated with Death in Aircraft Accidents and Incidents Using Data Mining Techniques (데이터 마이닝 기법을 활용한 항공기 사고 및 준사고로 인한 사망 발생 요인 및 패턴 분석)

  • Kim, Jeong-Hun;Kim, Tae-Un;Yoo, Dong-Hee
    • Journal of Digital Convergence
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    • v.17 no.9
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    • pp.79-88
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    • 2019
  • This study analyzes the influential factors and patterns associated with death from aircraft accidents and incidents using data mining techniques. To this end, we used two datasets for aircraft accidents and incidents, one from the National Transportation Safety Board (NTSB) and the other from the Federal Aviation Administration (FAA). We developed our prediction models using the decision tree classifier to predict death from aircraft accidents or aircraft incidents and thereby derive the main cause factors and patterns that can cause death based on these prediction models. In the NTSB data, deaths occurred frequently when the aircraft was destroyed or people were performing dangerous missions or maneuver. In the FAA data, deaths were mainly caused by pilots who were less skilled or less qualified when their aircraft were partially destroyed. Several death-related patterns were also found for parachute jumping and aircraft ascending and descending phases. Using the derived patterns, we proposed helpful strategies to prevent death from the aircraft accidents or incidents.

Disturbance regime and tree regeneration in kwangnung natural forest (광릉 자연림에서의 교란체제와 수목의 재생)

  • Cho, Do-Soon
    • The Korean Journal of Ecology
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    • v.15 no.4
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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.

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Assessing the impact of air pollution on mortality rate from cardiovascular disease in Seoul, Korea

  • Park, Sun Kyoung
    • Environmental Engineering Research
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    • v.23 no.4
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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.