• Title/Summary/Keyword: stand characteristics

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Assessment of Forest Vegetation Effect on Water Balance in a Watershed (산림식생에 따른 유역 물수지 영향 평가)

  • Kim, Chu- Gyum;Kim, Nam-Won
    • Journal of Korea Water Resources Association
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    • v.37 no.9
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    • pp.737-744
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    • 2004
  • In this study, to evaluate the effect of forest vegetation on the long-term water balance in a watershed, semi-distributed and physically based parameter model, SWAT was applied to the Bocheong watershed, and the variation of hydrological components such as evapotranspiration, surface flow, lateral flow, base flow, and total runoff was investigated with coniferous and deciduous forests, respectively. First, SWAT model was modified to simulate the actual plant growth pattern of coniferous trees which have the uniform value of leaf area index all the seasons of the year. The modified model was applied to the watershed that is assumed to have only one land cover in the whole watershed, and the variation of the water balance components was investigated for each land cover. It was found that coniferous forest affected the increase in evapotranspiration and decrease in runoff more than deciduous forest. However, the age and the density of stand, the location, and soil characteristics and meteorological conditions including the tree species should be also considered to examine the effect more quantitatively and to reduce the uncertainties in simulated output from the hydrological model.

Relation of Run- off and Canopy Interception to Rainfall in a Mixed Forest (혼효림(混淆林)에서 강우량(降雨量)이 유출량(流出量) 및 수관차단률(樹冠遮斷率)에 미치는 영향)

  • Lee, Sang Hwan
    • Journal of Korean Society of Forest Science
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    • v.35 no.1
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    • pp.36-38
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    • 1977
  • Some characteristics of rainfall interception and surface runoff from total rainfall at a forest stand mixed with Pinus densiflora and Alnus hirsuta in 1975 was analysised and the results obtained are as fellow; 1. The annual interception of rainfall by the forest canopy was 19.3 percent to annual rainfall 1,072.7mm. 2. The rate of rainfall interception in the dry season as spring and early summer was of 20 to 50 percent and less than 15 percent in the rainy season as summer. 3. About 50 percent of rainfall was intercepted in case of less than 10mm of every rainfall by the forest canopy and, in more than 20mm, about 20 percent intercepted.

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Analysis of Characteristics of some of Forest Environmental Factors on Debris Flow Occurrence - With a Pusan and Ulsan Metropolitan Areas - (토석류 유출에 기인하는 몇 가지 산림환경인자 분석 - 부산 및 울산광역시를 중심으로 -)

  • Lee, Hae-dong;Park, Jae-hyeon
    • Journal of Korean Society of Forest Science
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    • v.104 no.2
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    • pp.213-220
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    • 2015
  • This study was carried out to determine the distribution of factors as effected by debris flow in Ulsan and Pusan metropolitan areas because mainly debris flow caused by typhoons and local heavy rainfall events is mainly attributed to damage of human being ad property. The high risk degree of debris flow was to affected by east (20%), northeast (20%) and northwest (20%) slopes with stand age class with elevation (69%) of 100-200 (33%). Also, the risk was high in high erosion collapse degree with slope degree of $20-25^{\circ}$ with over 300 mm (100%) of maximum daily rainfall events and 50-100 mm (50%) or >100 mm (50%) of maximum hourly rainfall events with <5 km of stream path and <50 ha of catchment area. Landslide debris and wood residue flow was also related to igneous rocks (73%) and bank collapse types of debrs flow (57%).

Changes in Forest Disturbance Patterns from 1976 to 2005 in South Korea

  • Park, Pil Sun;Lee, Kyu Hwa;Jung, Mun Ho;Shin, Hanna;Jang, Woongsoon;Bae, Kikang;Lee, Jongkoo;Lee, Don Koo
    • Journal of Korean Society of Forest Science
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    • v.98 no.5
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    • pp.593-601
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    • 2009
  • Forest disturbances including forest fire, insect pests and diseases, landslides, and forest conversion from 1976 to 2005 were investigated to trace the changes of major forest disturbance agents and their characteristics over time in accordance with changes in natural and social environment in South Korea. While the damaged area by insect pests and diseases continuously decreased for the past 30 years, damaged areas by forest fire and landslide were fluctuating through years. The interval of large forest fires has become shorter with increased tree volume. The precipitation between January and April were significantly correlated with large fire occurrences as Pearson's correlation coefficient -0.400 (P=0.029). The composition of major insect pests and diseases damaging Korean forests has been changed continuously, and become more diversified. While damages by pine caterpillar (Dendrolimus spectabilis) and pine needle gall midge (Thecodiplosis japonensis) decreased, damage by introduced pests has been more serious recently. The change of precipitation pattern that brought more localized heavy rain or powerful typhoon resulted in the recent increase in landslide areas. The major land uses to induce forest conversion have been changed, reflecting the changes in industrial structure in South Korea as agriculture and mining in 1970s, mining and golf ranges classified in pasture in 1980s, and road and housing construction in 1990s and 2000s. Changes in forest disturbance patterns in South Korea show that a country's industrial development is jointly working with global warming on forest stand dynamics. Altering energy structure and land use pattern induced by industrial development accumulates forest volume and reforms microenvironments on forest floor, interacting with climate change, inducing shorter interval of large forest fire and changes in major species composition of forest insect pests and diseases.

Forest Community Classification and Stand Characteristics of Protected Area for Forest Genetic Resource Conservation in Mt. Cheongok (청옥산 산림유전자원보호구역의 산림군락분류 및 임분특성)

  • Shin, Jae-Kwon;Byun, Jun-Gi;Kim, Ju-Yeong;Choi, Seung-Ho;Kim, Dong-Kap
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.04a
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    • pp.47-47
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    • 2018
  • 본 연구는 청옥산 산림유전자원보호구역을 대상으로 총 49개의 고정방형구를 설치하여 식물사회학적 방법으로 산림군락분류와 임분특성을 분석하였다. 그 결과 총 9개의 식생단위로 분류되었으며 군락단위로는 신갈나무군락, 잣나무군락, 일본잎갈나무군락, 독일가문비나무군락으로 분류되었다. 신갈나무군락은 소나무군, 철쭉군, 고로쇠나무군, 미역줄나무군으로 세분되었으며, 고로쇠나무군은 박달나무소군과 고로쇠나무전형소군으로, 미역줄나무군은 애기감둥사초소군과 미역줄나무전형군으로 세분되었다. 9개의 식생단위의 층위별 중요치 분석결과를 보면 교목층에서 신갈나무가 32.2% 가장 높게 나타났으며 잣나무(10.1%), 소나무(10%), 일본잎갈나무(9.1%) 순으로 나타났고, 아교목층에서는 신갈나무 (18.9%), 당단풍나무(11.7%), 물푸레나무(8.9%), 잣나무(7.2%) 등이 높은 값으로 분석되었다. 관목층에서는 철쭉(12.2%)와 당단풍나무(8%)가 높게 분석되었으며 다른 수종들은 10% 미만의 값을 가졌다. 초본층에서는 조릿대(8.5%), 산숙국(6.6%)등이 높게 나타났다. 식생단위별 종다양성지수를 보면 식생단위 8인 일본잎갈나무군락이 1.76로 가장 높았으며, 박달나무소군 1.73, 소나무군 1.72, 철쭉군 1.71 순으로 분석되었다. 우점도는 모든 식생단위에서 0.2 이하로 다수의 종이 우점하는 것으로 나타났다.

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The study on implementation of modified SCORM standard for effective design of goal driven personalized e-learning system (목표지향 개인화 이러닝 시스템의 효율적인 설계를 위한 SCORM 표준의 수정제안 구현 연구)

  • Lee, MiJoung;Kim, KiSeok
    • The Journal of Korean Association of Computer Education
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    • v.12 no.3
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    • pp.41-51
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    • 2009
  • In this thesis, we suggested an e-learning model, which is named 'goal driven personalized e-learning system' to improve educational effects, and implemented it. The system makes the learner choose the learning goal which could be a motivational power for learning, so it enabled self-directed learning. In order to implement the system, we proposed new standards related to personalization by modifying SCORM 2004 standard. New standards stand for the statistics on learning objects usage, a goal for driving learning. and information of the contents model and the sequencing information model, which are parts of the system previously suggested. We implemented the system, and then proved that personalize e-learning is possible by showing that the system could offer a learning path individually to learners who have different characteristics.

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Performance Evaluation and Analysis of a VHF-UHF Blade Antenna (VHF-UHF 대역 블레이드 안테나의 성능 평가 및 분석)

  • Go, Jooseoc;Byun, Gangil;Kim, Kichul;Ju, Jeungmin;Choo, Hosung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.10
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    • pp.951-957
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    • 2013
  • In this paper, we propose a performance evaluation process of aircraft blade antennas. The process consists of various sub-processes that should be considered for a stable communication link with the base station. The process begins with the settlement of the ground shape and size to evaluate the impedance matching characteristics of a stand-alone antenna. Next, the main communications area of the antenna is determined by considering a flight scenario, and then the minimum gain requirements of the antenna are derived in the operating frequency band. Finally, the proposed evaluation process is applied for a commercial aircraft blade antenna. The results demonstrate that the proposed process is suitable to be adopted for the evaluation of aircraft blade antennas.

Acoustic and Physiological Characteristics of Pre-term and Full-term Infants' Cries (미숙아와 만삭아 울음의 음향 및 생리학적 특성)

  • Lee, Hyun-Sook;Pae, Jae-Yeon;Ko, Do-Heung
    • Phonetics and Speech Sciences
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    • v.2 no.2
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    • pp.37-42
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    • 2010
  • The purpose of this study is to first discriminate and assess those infants who appear healthy in appearance but who could face possible risk factors in the future and, secondly, to identify those infants who may have difficulties in their developmental stages. The subjects of this study consisted of 35 full-term infants (39-40 weeks) and 33 pre-term infants (34-35 weeks). The infants' voices were recorded for three minutes, for which EDIROL by Roland and a stand-type microphone made by SONY were used. This was done to discern the value of the Breath unit (B-unit) and the fundamental frequencies ($F_0$). It was found that there were significant differences in terms of F0 since the pre-term infants had higher F0 than the full-term infants, showing a result of 436.4 Hz for the full-term infants and 460 Hz for the pre-term infants (p<.05) There was an average rate of 4.01 for the full-term infants and 4.02 (SD=1.69) for the pre-term infants in shimmer. For NHR, it was observed .44 for the full-term infants and .50 for the pre-term infants, thus revealing no significant differences in these observations. This study shows that the crying of newborn babies is related to their physical conditions and it is a sensatory response to these conditions. Furthermore, this study could be helpful for the early detection and measurement of newborn babies who look clinically healthy but could be at risk through acoustic and physiological analyses.

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A study of the impact of the contemporary film industry on the game industry (현대 영화 산업이 게임 산업에 미치는 영향에 관한 연구)

  • Kim, Hak-Soo;Kang, Hyo-Soon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2011.10a
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    • pp.531-534
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    • 2011
  • It can be said that film and game industries take core parts of the comtemporary cultural industry. For consumers in modern industry, cultural industry is immensely significant as much as other industries. Because consumers are spending proportionally more money on experiential and emotional needs and less on basics such as food, housing, and clothes. Cultural industry is the one that can give us 'cultural satisfaction'. Some may say the film industry is different from the game industry in genre. However, we have no difficulty in finding many common characteristics between them since we are living in the world where any content or genre cannot stand alone and contents' boundaries diversify themselves to meet consumers' demand in daily basis. The purpose of this study is to look into the impact of the film industry on the game industry and to show how these different industries can coexist successfully by creating a synergy effect.

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Analysis of Influence Factors of Forest Soil Sediment Disaster Using Aerial Photographs - Case Study of Pyeongchang-county in Gangwon-province - (항공사진을 이용한 산지토사재해 영향인자 분석 - 강원도 평창군을 중심으로 -)

  • Woo, Choong-Shik;Youn, Ho-Joong;Lee, Chang-Woo;Jeong, Yongho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.11 no.1
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    • pp.14-22
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    • 2008
  • The forest soil sediment disasters occurred in Jinbu-myeon Pyeongchang county were investigated characteristics by the aerial photograph analysis. After digitizing from aerial photographs, forest soil sediment disaster sites were classified into 695 collapsed sites, 305 flowed sites and 199 sediment sites. DEM (Digital Elevation Model) were generated from 1 : 5,000 digital topographic map. Factors of geography, hydrology, biology, and geology were analyzed using DEM, geologic map, and forest stand map with aerial photographs by GIS spatial analysis technique. The forest soil sediment disasters were mainly occurred from southeastern slope to southwestern slope. In collapsed sit es, the average slope degree is $28.9^{\circ}$, the average flow length is 163.5m, the average area of drainage basin is 897$m^2$. In case of flowed sites, the average slope degree, flow length, the area of drainage basin and confluence order is $27.0^{\circ}$, 175m, 2,500$m^2$ and 1, respectively. In sediment sites, the average slope, flow length, the area of drainage basin and confluence order is $12.5^{\circ}$, 2,50m, 25,000$m^2$ and 4, respectively. Also the forest soil sediment disasters were occurred most of collapsed sites in the afforest land after felling and igneous rocks composed of granite.