• Title/Summary/Keyword: tree fall

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Effects of N. P. K. and sugar contents of different host-plants on the Biology of the fall web-worm, Hyphantria cunea DRURY (기주식물의 N.P.K. 및 Sugar의 함량이 흰불나방에 미치는 생물학적 영향)

  • Chung K. H.;Choi S. Y.
    • Korean journal of applied entomology
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    • v.5_6
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    • pp.39-46
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    • 1968
  • This experiment was conducted to study the effects of nitrogen, phosphorus, potassium, and sugar contents in the loaves of five different host plants on tile larval period, pupal period, pupal period, number of eggs in the ovary, and the tolerance of fall webworm larvae (Hyphantria cunea DRURY) to gamma-BHC. The results obtained in this study were as follows; 1. The contents of nitrogen, phosphorus, potassium, and sugar in tile leaves tested were varied with the species of the host plants and sampling time. 2. The larval and pupal periods were also varied with the host plants and generation of the fall webworm. The shortest larval and pupal periods were found in the mulberry and the longest ones in the apple tree, and their periods were shortened much more in the second generation. Except the relation between the larval period and tile nitrogen content in the first generation, significant correlation could not be found between their periods and nitrogen, phosphorus, potassium and surgar contents. The nitrogen contents among the other chemical factors, however, might be much more influenced on their developing period. 3. The pupal weight and number of eggs in the ovary were also varied with the host plants. sex, and generation. In both generations, the greatest pupal weight and number of eggs per female were found in the mulberry and the least ones in the apple tree. No significant correlation could be found between the pupal weight and number of eggs per female and the chemical factors analyzed. However, only the nitrogen content seemed to be highly related to the pupal weight and number of eggs. 4. The tolerance of the fall webworm larval to gamma-BHC was highly varied with the host plants. The host order o( the larval tolerance level to gamma-BHC was box-elder, popla, platanus, apple tree, and mulberry. There was no significant correlation between the larval tolerance to the BHC and the chemical factors analyzed. However, the larvae fed on the host plant with higher pottassium content were shown a tendency to be higher tolerant.

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An Analysis of Relationships between Plant Growth and Temperature Characteristics Measured with Thermographic Camera (식물의 성장과 열화상카메라로 측정된 열적 특성과의 연관성 분석)

  • Park, Sang-Mi;Nam, Da-Hyun;Kim, Ji-Hyung;Jo, Geon-Young;Kim, Ha-Yang;Kim, Jeongbae
    • Journal of the Korean Solar Energy Society
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    • v.36 no.2
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    • pp.1-7
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    • 2016
  • This study was experimentally performed to analyze the growth characteristics of a plant(wax tree or privet) using the surface temperature measured from thermal images captured using a thermal camera with water and cider. To do that, this study measured every each 12 hours the surface temperature and the stem temperature of leaves attached to the plant sample until the plants wilt on summer season in the laboratory room. From the experimental results, this study revealed that the temperature of front and back of the leaves is a little different due to the pore. The mean surface temperature of a leaf in cider is $0.52^{\circ}C$ higher than that of a leaf in water. The phenomena that the leaves of plants fall could be also demonstrated using the surface temperature. Before a leaf is falling from the tree, the temperature of the stem is lowered about $2^{\circ}C$ than those of other parts in a leaf. This result can be validated from previous result performed in University of Wisconsin.

Biotic and spatial factors potentially explain the susceptibility of forests to direct hurricane damage

  • Kim, Daehyun;Millington, Andrew C.;Lafon, Charles W.
    • Journal of Ecology and Environment
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    • v.43 no.4
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    • pp.364-375
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    • 2019
  • Background: Ecologists continue to investigate the factors that potentially affect the pattern and magnitude of tree damage during catastrophic windstorms in forests. However, there still is a paucity of research on which trees are more vulnerable to direct damage by winds rather than being knocked down by the fall of another tree. We evaluated this question in a mixed hardwood-softwood forest within the Big Thicket National Preserve (BTNP) of southeast Texas, USA, which was substantially impacted by Hurricane Rita in September 2005. Results: We showed that multiple factors, including tree height, shade-tolerance, height-to-diameter ratio, and neighborhood density (i.e., pre-Rita stem distribution) significantly explained the susceptibility of trees to direct storm damage. We also found that no single factor had pervasive importance over the others and, instead, that all factors were tightly intertwined in a complex way, such that they often complemented each other, and that they contributed simultaneously to the overall susceptibility to and patterns of windstorm damage in the BTNP. Conclusions: Directly damaged trees greatly influence the forest by causing secondary damage to other trees. We propose that directly and indirectly damaged (or susceptible) trees should be considered separately when assessing or predicting the impact of windstorms on a forest ecosystem; to better predict the pathways of community structure reorganization and guide forest management and conservation practices. Forest managers are recommended to adopt a holistic view that considers and combines various components of the forest ecosystem when establishing strategies for mitigating the impact of catastrophic winds.

Impact of Environmental Factors and Altitude on Growth and Reproductive Characteristics of Teak (Tectona grandis Linn. f.) in Southern India

  • Krishnamoorthy, M.;Palanisamy, K.;Francis, A.P.;Gireesan, K.
    • Journal of Forest and Environmental Science
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    • v.32 no.4
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    • pp.353-366
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    • 2016
  • The effect of different environmental conditions and altitudes on the growth and reproductive characteristics in 12 teak plantations at 4 different blocks (Cauvery canal bank, Topslip and Parambikulam (Tamil Nadu), Nilambur and Wayanad (Kerala) of Southern India was investigated. The annual rainfall and mean monthly temperature of the study areas varied significantly from 1390 to 3188 mm and 16 to $38^{\circ}C$ respectively. The teak plantations in Cauvery canal bank which grow in continuous moisture condition (8-10 months) retain the leaf for longer period due to moisture resulting continuous supply of photosynthates leads to fast and outstanding growth. The girth at breast height (GBH) of 34-years-old tree in canal area was similar to that of 40 to 49-years-old trees in other locations, indicating that teak plantations with regular watering and silvicultural practices may be harvested at the age of 30 years. The leaf fall, flowering and fruiting showed significant variations in different teak plantations due to environmental factors and altitudes. It was found that increase of rainfall enhances number of flowers in the inflorescence in teak. Tholpatty (block-IV) showed more flowering in a inflorescence (3,734-3,744) compared to other plantations (1,678-3,307). Flowering in Nilambur and Wayanad coincided with heavy rainfall resulting low fruitset (1.1-2.3%) probably heavy rainfall ensuing restriction of pollinators for effective pollination. On the other hand, flowering in Cauvery canal bank (Block-I) was not coincided with high rainfall exhibited high fruitset (2-3%). About 66 to 76% of the fruits in different plantations were empty, and it is one of the main reasons for poor germination in teak. The seeds of Topslip and Parambikulam (Block-II) showed higher seed weight, maximum seed filling and good germination indicating that the environmental factors and altitude play significant role in fruit setting and seed filling in teak. In addition, the teak plantations in Topslip and Parambikulam showed good growth suggesting that plantations in the altitude range of approximately 550-700 m may be suitable for converting into seed production areas for production of quality seeds.

Eco Recycling measure from the waste of tree in Road Construction site (도로 건설현장 임목폐기물 친환경 재활용 방안)

  • Lee, Yong-Soo;Park, Eun-Ho;Ryu, Sang-Hun
    • Proceedings of the KAIS Fall Conference
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    • 2011.12b
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    • pp.584-586
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    • 2011
  • 본 논문에서는 도로 건설현장에서 발생하는 임목폐기물을 도로 보호길 어깨 포설에 재활용 하는 친환경 방안을 제시하였다. 기존에는 임목폐기물을 폐기물로 분류하여 폐기물 전문업체를 통해 위탁 처리하였으나, 임목폐기물의 효율적인 자원 낭비를 방지하고자 도로 보호길 어깨에 임목폐기물을 파쇄하여 포설하고자 한다. 포설 방법은 보호길 어깨를 굴착하여 파쇄칩을 포설 및 다짐한 후 친환경성 접착제를 살포한다. 위 활용 방안의 가능성을 입증하기 위해 우수 침식시험기를 자체 제작 후 실내시험을 실시하였다. 침식 시험기를 이용한 시험 결과 현장 적용이 가능하다는 결론을 얻었다.

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Quantitative Risk Assessment based on Fault Tree Analysis for Gangform Accident (갱폼 재해의 FTA를 통한 정량적 위험성 산정에 관한 연구)

  • Ham, Young Jong;Kee, Jung Hun;Park, Jong Yil
    • Journal of the Korean Society of Safety
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    • v.35 no.4
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    • pp.40-47
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    • 2020
  • Although gangform has good workability due to the integration of outer wall forms and working platforms, 22 workers were died from 21 gangform related accidents during 2012 to 2016. Quantitative risk assessment is required for evident based prevention measure selection. In this study, based on 52 accident data from 2004 to the first half of 2019, FTA is conducted for probabilities of direct causes and their contribution to accidents. Three stages are considered; gangform installation, dismantling and lifting, and using. The effectiveness of countermeasures is evaluated through minimum cut set, RAW and RRW. Complete assembly of gangform on the ground level, detailed planning, and fall prevention device are suggested as prevention measures for installation, dismantling and lifting, and using stages, respectively.

Ecological Studies on the Seed Production and Natural Regeneration in Hornbeam Forest (개서나무林의 種子生産과 天然更新에 관한 生態學的 硏究 1. 기초연구)

  • Rim, Young-Deuk;Ho-Kam Kang;Nobukazu Nakagoshi
    • The Korean Journal of Ecology
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    • v.14 no.1
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    • pp.1-7
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    • 1991
  • This study was carried out to estimate the seed crop of Carpinus forest in Piagol of Mt. Chiri for six years and the results obtained were as follows; Upper two layers of Capinus forest were dominated by C. tschonoskii and Subfall tree layer ranging from 15.40 to 17.20 m in height. The distribution of seed weight of C. tsconoski was skewed to light weight classes. Most seeds fall in November. The best crop was shown in 1984, while virtually no crops in 1985. Since 1985, annual seed crop increased gradually.

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Efficient Ontology Merging Algorithm Using Tree (트리를 이용한 효율적인 온톨로지 병합 알고리즘)

  • Kim, Young-Tae;Lim, Jae-Hyun;Kong, Heon-Tag;Kim, Chi-Su
    • Proceedings of the KAIS Fall Conference
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    • 2010.05a
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    • pp.404-407
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    • 2010
  • 일반적으로 온톨로지는 관심 있는 특정 도메인에 대해 생성되므로 넓은 문제 영역에서 단일 온톨로지가 응답하는 것을 기대할 수 없다. 이것은 큰 작업에서 상이한 온톨로지의 데이터를 사용할 필요가 있음을 의미한다. 또한 대부분의 온톨로지는 한 사람이나 작은 그룹에 의해 개발되고, 그래프가 아닌 트리로 생각할 수 있다. 본 논문에서는 트리를 이용하여 온톨로지를 구축하고, 이해하고, 처리하는 효율적인 방법을 보이고자 한다. 온톨로지 병합 오퍼레이션의 정의를 위해 온톨로지의 구조, 구성 요소, 표현을 자세하게 정의하고, 두 온톨로지를 병합하는 방법에 대한 세부 사항을 보인다.

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False Positive Reduction for IDS using Decision Tree (결정트리를 이용한 IDS의 False Positive 감소기법)

  • Jeong, Kyeong-Ja
    • Proceedings of the KAIS Fall Conference
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    • 2010.05a
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    • pp.455-458
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    • 2010
  • 침입탐지시스템은 공격이라고 판단되면 경보를 발생하여 보안 관리자에게 알려주거나 자체적으로 대응을 하게 된다. 그러나 이러한 경보들 중에 오경보가 많이 포함되어 있어 침입탐지시스템의 성능을 저하시킬 뿐 아니라 대량의 경보자체가 보안메커니즘에 방해가 되고 있다. 특히 오경보중 False Positive가 전체 오경보의 대부분을 차지하고 있다. 즉, False Positive는 정상 행위를 침입행위로 오인하여 판단하는 것을 의미한다. 경보들 중 이러한 오경보들은 네트워크 전반에 걸친 보안 서비스의 질을 하락시키는 원인이 된다. 따라서 침입탐지시스템의 성능향상을 위해서는 이러한 오경보 문제가 반드시 해결되어야 한다. 본 논문에서는 침입탐지시스템의 오경보를 감소시키는 결정트리 기반 오경보 분류모델을 제안하였다. 결정트리 기반 오경보 분류 모델은 침입탐지시스템의 오경보율을 감소시키고 침입탐지율을 향상시키는 역할을 수행한다는 것을 확인할 수 있었다.

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A Study on the Tree Dimensional Object Trace Algorithm using dual-Camera (이중카메라를 이용한 객체 추적 알고리즘에 대한 연구)

  • Jang, Jung-Hwa
    • Proceedings of the KAIS Fall Conference
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    • 2010.05a
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    • pp.483-486
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    • 2010
  • 단일 카메라를 통하여 실시간으로 입력되는 객체의 추적은 환경의 제약을 많이 받는다. 입력되는 영상에서의 움직임이 있는 객체는 단일하여야 하며, 동시에 많은 움직임이 발생하면 추적하고자 하는 객체를 구분하기 어려워진다. 본 논문에서는 동일공간을 감시하는 두 대의 카메라가 서로 데이터를 주고 받으며 추적하고자 하는 특정객체를 오류 없이 추적할 수 있는 방법을 제시하였다. 실시간 객체 추적은 입력되는 영상에서 객체의 위치를 가장 빠르게 검색하기 위한 고속탐색 알고리즘이 필요하다. 본 논문은 실시간영상에서 객체의 움직임을 추출하고 추적을 위하여 각각 위치가 다른 두 대의 카메라가 상호 협력하면서 객체 추적에 대한 연산을 현저하게 줄일 수 있었다. 또한 객체의 움직임이 많은 공간에서도 추적하고자 하는 특정객체를 잃어버리지 않고 추적하였다. 실험결과, 제안한 방법은 97% 이상의 높은 객체 추적율을 보였다.

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