• Title/Summary/Keyword: TREE RING

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Stochastic Simulation Model for non-stationary time series using Wavelet AutoRegressive Model

  • Moon, Young-Il;Kwon, Hyun-Han
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.1437-1440
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    • 2007
  • Many hydroclimatic time series are marked by interannual and longer quasi-period features that are associated with narrow band oscillatory climate modes. A time series modeling approach that directly considers such structures is developed and presented. The essence of the approach is to first develop a wavelet decomposition of the time series that retains only the statistically significant wavelet components, and to then model each such component and the residual time series as univariate autoregressive processes. The efficacy of this approach is demonstrated through the simulation of observed and paleo reconstructions of climate indices related to ENSO and AMO, tree ring and rainfall time series. Long ensemble simulations that preserve the spectral attributes of the time series in each ensemble member can be generated. The usual low order statistics are preserved by the proposed model, and its long memory performance is superior to the direction application of an autoregressive model.

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Design and Implementation of Interconnection Network Drawing System on WWW (웹 상에서의 상호연결망 드로잉 시스템의 설계 및 구현)

  • 이윤희;홍석희;이상호
    • Proceedings of the Korean Information Science Society Conference
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    • 1998.10b
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    • pp.667-669
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    • 1998
  • 그래프 드로잉 시스템이란 주어진 그래프에 대하여 그 그래프가 가진 어떤 특성을 가시화하여 그래픽하게 표현해 주는 소프트웨어 시스템을 말한다. 본 논문에서는 Java를 사용하여 WWW(World Wide Web) 상에서의 상호연결망 그래프의 대칭적 드로잉을 수행하는 그래프 드로잉 시스템을 소개한다. 이 시스템을 Ring, HyperCube, Butterfly와 같은 대표적인 상호연결망 그래프에 대한 기존의 드로잉과 대칭성을 잘 나타내 주는 드로잉을 동시에 보여주며, 또한 HyperCube, HyperTree, Pyramid와 같이 그 모양을 입체적으로 나타낼 수 있는 그래프에 대해서는 원근법을 사용한 3차원 드로잉을 하고 X,Y,Z 축에 따라 이를 회전시켜 그래프에 대한 이해도를 높였다.

Estimation of Old Climate and the Radial Growth of Trees since 1782 in South Korea (1782 年 以來 韓國의 古氣候와 수種의 肥大成長推定)

  • Lee, Myung Soon;Kwang Soo Paik;Yang-Jai Yim
    • The Korean Journal of Ecology
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    • v.8 no.4
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    • pp.215-223
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    • 1985
  • The fluctuation of old climate was studied by the analysis of radial growth in trees, since 1782. For the effects of environmental factors on the radial growth, the authors proposed the relative radial growth(Rg) concept modified the emperical equation of Fritts (1969) as follow: Yt=aebt Yt: theoretical annual ring width time t a and b: constants in different tree species Rg=Yt/Yt Rg: ratio of real radial growth to theoretical growth with age Yt: real annual radial growth Used the Rg value, the relationship between climatic conditions and the radial growth during 70 years was investigated, and the fluctuations in climate during the last 200 years with the historical records was detected.

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The Influence of Ring-Back-Tone(RBT) on Evaluation of the Phone-call Receiver's Personality (통화 연결 음악이 통화 상대자의 개성 판단에 끼치는 영향)

  • Suk, Hyeon-Jeong;Kim, Bo-Min;Kwon, Moon-Young;Jeong, Sang-Hoon
    • Science of Emotion and Sensibility
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    • v.10 no.3
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    • pp.343-354
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    • 2007
  • Two experiments were carried out in order to investigate the influence of Ring-Back-Tone(RBT) music on the evaluation of the phone-call receiver's personality in dimensions of Openness, Extroversion, and Neuroticism. In a preliminary experiment, the subjects listened to 17 RBT music stimuli in random order and assessed the personality associated with liking for each music using the 12 personality traits(N=15). Among the 17 RBTs, three were selected to be used in main experiment and they were distinguished from each other in terms of the tree personality dimensions(p<0.001). In main Experiment, it was hypothesized that the evaluation of phone-call receivers' personalities would be influenced by the personality of RBT music. Therefore, in the main experiment, the subjects were divided into four groups and each listened to one of the three RBTs or to a plain ringing tone(control group) until the receiver(the experimenter) answered the call. After interviewing the receiver, subjects evaluated her personality using the 12 traits. The empirical results provide evidence that the RBT influences the judgment of phone-call receiver's personality in terms of the three personality dimensions(p<0.001), supporting the hypothesis. In addition, it is found that there is a positive correlation between the personalities of RBT music and the phone-call receivers' personalities elaborating the affirmative result for the hypothesis(r=0.753, openness, p<0.01, r=0.753, extroversion, p<0.01; r=0.265, neuroticism).

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Studies on the Hardness of Woods (목재(木材)의 경도(硬度)에 관(關)한 연구(硏究))

  • Hong, Soon-Il;Lee, Won Yong
    • Journal of Forest and Environmental Science
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    • v.8 no.1
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    • pp.21-33
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    • 1992
  • This study was performed to investigate the hardness of wood related to the wood surface, sap and heartwood, early and latewood, specific gravity, annual ring width and moisture content on major Korean tree species such as Pinus koraiensis, Abies holophylla, Larix leptolepis and Quercus valiabilis. The results were summarized as follows: 1. The arithmetic mean values of wood hardness on cross section were respectively $8.0kg/mm^2$ on Quercus valiabilis, $7.4kg/mm^2$ on Larix leptolepis, $5.1kg/mm^2$ on Pinus koraiensis and $4.7kg/mm^2$ on Abies hollophylla. 2. Generally hardness of wood on cross section was greater than the others and the proportion of cross section hardness to radial was respectively 2.8 on Quercus valiabilis, 2.6 on Larix leptolepis, 3.8 on Pinus koraiensis, and 4.1 on Abies holophylla and that proportion was tend to be decrease as specific gravity increased. 3. It was recognized that the hardness of sap and heartwood was different from each of the tree species and generally heartwood hardness was somewhat greater than sapwood. 4. Generally latewood hardness with in a ring was greater than earlywood and the proportion of earlywood hardness to latewood decreased as specific gravity increased. 5. The relations between hardness of wood and specific gravity show a high positive correlation on all sample tree species. 6. The values of hardness decreased with increasing annual ring width. 7. Hardness of wood on Abies holophylla was greatest in oven dried wood and it was decreased as moisture content increased, but not changed with moisture content abve F.S.P.. The proportion of oven dried wood hardness to green are respectively 3.0 on cross, 2.4 on radial and 1.9 on tangential section.

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A Dendroclimatic Analysis on Abies koreana in Cheonwang-bong Area of Mt. Chiri, Korea (지리산 천왕봉지역 구상나무의 연륜기후학적 해석)

  • 박원규;서정욱
    • The Korean Journal of Quaternary Research
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    • v.13 no.1
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    • pp.25-33
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    • 1999
  • The relationships between climate (monthly precipitation and temperatures) and tree-ring growth of Korean fir (Abies koreana) growing at subalpine (1,600∼l,700m) zone on the south slope, Joong-Bong and the north slope, Changgun-Bong in the Cheonwang-bong area in Chiri mountains in the southern Korea were analyzed. Two cores from each of 10∼12 trees were extracted. The relationship between tree-ring(standardized) chronologies and climate was analyzed by the response-function method. Climate variables could explain 45.9∼53.8% of total variance in the chronologies. The precipitation response function of Korean fir were similar at both sites in overall ; positive for March∼May and August, and negative for February and July. The south-slope fir of Joong-Bong possessed higher negative temperature response function for February and August than north-slope one. The positive response function for April temperature was significant for both sites. In contrary to other subalpine species (e.g., Pinus koraiensis and Taxus cuspidata) in South Korea, whose growths are positively correlated with temperature in most seasons, the growths of Korean fir trees in Mt. Chiri appeared to be mainly limited by the moisture regime of spring prior to the cambial growth and early growing season.

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Vegetation Type and Stand Structure of Pinus densiflora Forests in Kangwon Northern Region in Korea (강원북부지역 소나무림의 식생유형과 임분구조)

  • Lee, Kwang-Soo;Kim, Suk-Kwon;Bae, Sang-Won;Lee, Jung-Hyo;Shin, Hyun-Cheol;Jung, Mun-Ho;Moon, Hyun-Shik;Bae, Eun-Gi
    • Journal of agriculture & life science
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    • v.43 no.6
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    • pp.7-17
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    • 2009
  • The objectives of this study were to analyze vegetation type and stand structure of the red pine (Pinus densiflora) in Kangwon northern region for stable and sustainable management forests. The pine forests in study sites were classified into 3 communities, 5 groups, and 2 subgroups, total 7 vegetation units. Species with constance degree of more than 61% were P. densiflora, Quercus mongolica, Lindera obtusiloba, Spodiopogon sibiricus, Atractylodes japonica, Rhododendron mucronulatum, and Carex humilis. They were showing different characteristics by pattern according to their growing district. In the importance value (I.V.) analysis of each layer, P. densiflora showed highly in tree layer while in other layers Quercus spp. was high. Especially, young P. densiflora tree hardly appeared in the herb layer, but broad-leaved trees and shrub species showed high I.V.. Furthermore, the annual ring growth of P. densiflora was reduced while that of Q. spp. increased. According to analysis of stand structures and annual ring growths, it is considered that appropriate silvicultual practice methods should be employed to remove rival broad-leaved species for maintenance of sustainable red pine forests considering the characteristics of each stand.

Trend and Shift Analysis for Hydrologic and Climate Series (수문 및 기후 자료에 대한 선형 경향성 및 평균이동 분석)

  • Oh, Je Seung;Kim, Hung Soo;Seo, Byung Ha
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.4B
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    • pp.355-362
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    • 2006
  • Several techniques of MK test, Spearman's Rho test, Linear Regression test, CUSUM test, Cumulative Deviation, Worsley Likelihood Ratio test, Rank Sum test, and Students' t test were applied to detect the trends of slope and shift which exist in hydrologic and climate time series. The time series of annual rainfall, inflow, tree ring index, and southern oscillation index (SOI) were used and the trends of these series were compared in the study. From the results, it can be found that the data could be classified into two categories such as linear trend and shift. 4 series data of 8 rainfall series which reveal the trend show the shift and 8 series data of 18 tree ring index and March and April series of monthly SOI data show shift. Moreover, ADF test and BDS test were used to test stationarity and non-linearity of the data. In conclusion, through the study, various trend analysis techniques were compared and 6 kinds of characteristics which can exist in hydrologic time series were identified.

Anatomical and Physical Properties of Pitch Pine (Pinus rigida Miller) - The Characteristics of Stem, Branch, Root and Topwood - (리기다소나무(Pinus rigida Miller)의 목재해부학적(木材解剖學的) 및 물리학적성질(物理學的性質)에 관(關)한 연구(硏究) - 간(幹), 지(枝), 근(根), 초두목(梢頭木)의 특성(特性)을 중심(中心)으로 -)

  • Lee, Phil Woo
    • Journal of Korean Society of Forest Science
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    • v.16 no.1
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    • pp.33-62
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    • 1972
  • Pitch pine (Pinus rigida Miller) in Korea has become one of the major silvicultural species for many years since it was introduced from the United States of America in 1907. To attain the more rational wood utilization basical researches on wood properties are primarily needed, since large scale of timber production from Pitch Pine trees has now been accomplishing in the forested areast hroughout the country. Under the circumustances, this experiment was carried out to study the wood anatomical, physical and mechanical properties of Pitch Pine grown in the country. Materials used in this study had been prepared by cutting the selected pitch pine trees from the Seoul National University Forests located in Suwon. To obtain and compare the anatomical and physical properties of the different parts of tree such as stem, branch, top and rootwood, this study had been divided into two categories (anatomical and physical). For the anatomical study macroscopical and microscopical features such as annual ring, intercellular cannal, ray, tracheid, ray trachid, ray parenchyma cell and pit etc. were observed and measured by the different parts (stem, branch, root and topwood) of tree. For the physical and mechanical properties the moisture content of geen wood, wood specific gravity, shrinkage, compression parallel to the grain, tension parallel and perpendicular to the grain, radial and tangential shear, bending, cleavage and hardness wree tested. According to the results this study may be concluded as follows: 1. The most important comparable features in general properties of wood among the different parts of tree were distinctness and width of annual ring, transition from spring to summerwood, wood color, odor and grain etc. In microscopical features the sizes of structural elements of wood were comparable features among the parts of tree. Among their features, length, width and thickness of tracheids, resin ducts and ray structures were most important. 2. In microscopical features among the different parts of tree stem and topwood were shown simillar reults in tissues. However in rootwood compared with other parts on the tangential surface distinctly larger ray structures were observed and measured. The maximum size of unseriate ray was attained to 27 cell ($550{\mu}$) height in length and 35 microns in width. Fusiform rays were formed occasionally the connected ray which contain one or several horizontal cannals. Branchwood was shown the same features like stemwood but the measured values were very low in comparing with other parts of tree. 3. Trachid length measured among the different parts of tree were shown largest in stem and shortest in branchwood. In comparing the tracheid length among the parts the differences were not shown only between stem and rootwood, but shown between all other parts of tree. Trachid diameters were shown widest in rootwood and narrowest in branchwood, and the differences among the different parts were not realized. Wall thickness were shown largest value in rootwood and smallest in branchwood, and the differences were shown between root and top or branchwood, and between stem and branch or top wood, but not shown between other parts of tree. 4. Moisture contents of green wood were shown highest in topwood and lowest in heartwood of stem. The differences among the different parts were recognized between top or heartwood and other parts of tree, but not between root and branchwood or root and sapwood. 5. Wood specific gravities were shown highest in stem and next order root and branchwood, but lowest in topwood. The differences were shown clearly between stemwood and other parts of tree, but not root and branchwood. However the significant difference is realized as most lowest value in topwood. 6. In compression strength parallel to the grain compared among the different parts of tree at the 14 percent of moisture content, highest strength was appeared in stem, next order branch and rootwood, but lowest in topwood. 7. In bending strength compared among the different parts of tree at the 14 percent of moisture content clearly highest strength was shown in branchwood, next order stem and root, but lowest in topwood. Though the branchwood has lower specific gravity than stemwood it was shown clearly high bending strength.

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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.