• Title/Summary/Keyword: Burned Area

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Change for Engineering Properties of Top Soils in the Wildfire Area (산불발생지역에서 상부토층의 공학적 특성 변화)

  • Song, Young-Suk;Chae, Byung-Gon;Kim, Kyoung-Su
    • The Journal of Engineering Geology
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    • v.17 no.2 s.52
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    • pp.225-233
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    • 2007
  • The engineering properties of surface soils in natural terrain are changed due to wildfire. This change of engineering properties induced by wildfire is related to landslides occurrence. To investigate the change of soil properties caused by wildfire, the various soil tests are performed. The soil samples are obtained from the recently burned slopes of Yangyang area, Kangwon Province. The soil samples obtained from the burned slopes are classified into three types depending on the burning grade: the perfect burning grade, the intermediate burning grade, the non-burning grade. As the result of tests, the specific gravity and the dry unit weight of soils obtained from perfect and alternative burning grades are less than those of soils obtained from non-burning grade. It judges that an electronic force, ionic components and of soils are changed and organic matters in soils are burned by wildfire. The permeability of soil obtained from alternative burning grade is the lowest and that of soil obtained from perfect burning grade is the highest. The water-repellent layer is formed on soil surface by wildfire. The water-repellent layer is existed at the area of alternative turning grade, while the layer is not existed at the area of perfect burning grade. The water-repellent layer is collapsed in high temperature more than about $400^{\circ}C$.

Ecological Studies on Vegetation Recovery of Burned Field after Forest Fire (산화적지의 식생회복에 관한 생태학적 연구)

  • Kang, Sang Joon;Jong Tai Lee
    • Journal of environmental and Sanitary engineering
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    • v.5 no.1
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    • pp.54-62
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    • 1990
  • The recovery of vegetatiion and soil properties in the burned fields after forest fire were studied in Chung Cheong Buk Do area, Korea, from July 23 to 28, 1981. Miscanthus sinensis var. purpurascens, Carex humilis and Lespedeza bicolor were dominant species in the burned field of the second year after forest fire as well as unburned field. Especially, Lespedeza bicolor was gradually grown to the dominant species. Lespedeza bicolor, Carex humilis and Miscanthus sinensis var. purpurascens were the dominant species in the burned field of the fifth year after forest fire. Biological spectra of the burned fields were similar to the umburned fields with $H-e-D_1-R_5$ or $Ph-e-D_1-R_5$ from the second year after forest fire. Accordingly, biological spectra were recovered to the unburned fields from the second year. Degree of successiion was DS=423 in the burned field and DS=524 in the unburned field in 1981. The DS of the burned fields was gradually increased and recovered to be similar to the unburned from the second year. In the species diversities and evenness index, H,e and $\beta$ of the burned field in 1981 were higher and $\lambda$ was lower than the unburned field, but all of the indices were recovered to the unburned field from the second or third years. Accordingly, the vegetation of the first year was the complex community in view floristic composition, but it was recovered to the simple community as unburned field fromthe second or third years. In the soil preperties, pH, total nitrogen, available phosphorus, exchangeable potassium, exchangeable calcium and exchangeable magnesium were increased and organic matter was decreased due to forest fire, and then was recovered to the unburned field from the second or third years. The vegetation and soil properties of the burned field after forest fire were similary recovered to the unburned field from the second or third years. Accordingly, there was a close relationship between the trend of vegetation recovery and the changes of soil characteristics after forest fire.

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Characteristics Analysis of Burned tree by Terrestrial LiDAR in Forest Fired Area of Pinus densiflora (지상라이다를 활용한 소나무 산불피해지의 임목 피해특성 분석)

  • Kang, Jin-Taek;Ko, Chi-Ung;Yim, Jong-Su;Lee, Sun-Jeoung;Moon, Ga-Hyun;Lee, Seung-Hyun
    • Korean Journal of Remote Sensing
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    • v.36 no.6_1
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    • pp.1291-1302
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    • 2020
  • To verify the field-effectiveness of Terrestrial Laser Scanner (TLS), a terrestrial LiDAR was deployed to examine the damage properties of woods in forest fire area, then the data was compared with the results surveyed by a forestry expert. Four sample plots (30 m × 50 m, 0.15 ha) were set from the foot to the top of the mountain, and DBH, height, clear length, burned height, and crown length were investigated. Next, TLS collected information on damage characteristics found in the sample plots. This information was then compared with that amassed by the expert. The expert and the TLS survey results showed 30.8 cm and 29.9 cm for DBH, 15.8 m and 17.5 m for tree height, 8.4 m and 8.4 m for clear length, 4.0 m, 3.5 m for burned height, and 7.4 cm and 9.1 cm for crown length. With the exceptions of height and clear length, no notable discrepancy was observed between two methods. H/D ratio, CL/H ratio, and BH/CL ratio, all of which contribute to stability and decay rate of the stand, from the two methods were also compared. The human survey rated each ratio (H/D, CL/H, BH/CL in order) 51.3%, 47.1%, and 53.6%, while the TLS presented the results of 58.8%, 52.0%, and 38.7%.

Ecological Studies on the Burned Forest - On the Germination of Remained Seed on Burned Area - (산화적지(山火跡地)의 생태학적(生態學的) 연구(硏究) - 산화후(山火後)의 잔여종자(殘餘種子) 발아율(發芽率)에 대(對)하여 -)

  • Kim, Ok Kyung
    • Journal of Korean Society of Forest Science
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    • v.10 no.1
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    • pp.29-39
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    • 1970
  • Forest fires often destory forests that have taken years to grow in a few minutes. Forest fire therefore, is an important problem in forest management and have caused heavy losses to the nations economy. In order to resolve this problem many investigations have been made in many countries. However, ecological studies on the forest after accidental fire have not yet been made in Korea. In order to conduct such a study, a burned area on Mt. Samak which is located at Dukduwon-ri, Seo-myon, Chunsung-gun, Kangwon-do, was chosen as experimental plot in 1967. The remaining seeds were collected from the burned area, and investigations on their germination rate and their productivity were made comparing to those of the seeds of undemaged area, and following results were obtained. 1. The number of seed collected from the control plots were 740 while it was 537 from the test plots (Table 3, 4). It was considered that this difference between burned and unburned area was mainly due to the fact that some of the seeds had been burnt by the fire, and the unfavorable environmental conditions in the burned area was also considered to be a reason. In the germination rate in the control plots showed 28.1% while it was 3.2% in the test plots. This difference was considered to be due to complete loss of viability of the seed by burning and high heat. 2. In the test plots, sixteen seeds of the Alnus japonica were collected and six of these seeds germinated (index number 100) which was the highest germination rate among the species of collected seeds. From these results, it was considered that a high temperature (above $150^{\circ}C$) caused reduction of the germination rate (Quadrat. 1.2). Seeds of Carex lanceolata var. Nana, were appeared much more in the higher plots than in the lower plots and it seemed to be due to the fact that the forest floor plants were much more abundant in the lower plots than in the higher plots which is covered with shrubbery. And some small seeds midght be able to avoid the effect of fire being burried in the soil or under the gravel. 3. With Pinus densiflora, 43 seeds were collected, and 11 of these germinated in the control plots. However in the test plots, 11 seeds were collected and no seed germinated. This shows that the Pinus densiflora was the weakest in resisting to heat among the observed species in this study. 4. Without exception the germination rate showed a higher index in the herbs than in the woody plants and it is believed that the herbs produced more seed than the wood plants because of the abundance of herbs colony.

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Analysis of Slope Hazard-Triggering Rainfall Characteristics in Gangwon Province by Database Construction (DB구축을 통한 강원지역 사면재해 유발강우특성 분석)

  • Yune, Chan-Young;Jun, Kyoung-Jea;Kim, Kyung-Suk;Kim, Gi-Hong;Lee, Seung-Woo
    • Journal of the Korean Geotechnical Society
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    • v.26 no.10
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    • pp.27-38
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    • 2010
  • In every summer season, most of the slope failures and debris flows occurr due to seasonal rain, typhoon, and localized extreme rainfall in Gangwon Province where 83% of the area is of mountain region. To investigate the slope-hazard triggering rainfall characteristics in Gangwon Province, slope hazard data, precipitation records, and forest fire data were collected and the DATABASE was constructed. Analysis results based on the DATABASE showed that many slope hazards occurred when there was little rainfall and the preceding rainfall had more effect on the slope hazard than the rainfall intensity at the day of hazard. It also showed that the burned area by forest fire was highly susceptible to slope hazard with low rainfall intensity, and the slope hazard in burned area showed highest frequency, especially, under the rainfall below 2-year return period.

Effects of Topical Tamoxifen on Wound Healing of Burned Skin in Rats

  • Mehrvarz, Shaban;Ebrahimi, Ali;Sahraei, Hedayat;Bagheri, Mohammad Hasan;Fazili, Sima;Manoochehry, Shahram;Rasouli, Hamid Reza
    • Archives of Plastic Surgery
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    • v.44 no.5
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    • pp.378-383
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    • 2017
  • Background This study aimed to assess the effects of the topical application of tamoxifen on wound healing of burned skin in Wistar rats by evaluating 3 healing characteristics: fibrotic tissue thickness (FTT), scar surface area (SSA), and angiogenesis in the healed scar tissue. Methods Eighteen male Wistar rats were used in this study. A third-degree burn wound was made on the shaved animals' back, measuring $2{\times}2{\times}2cm$. In the first group, a 2% tamoxifen ointment was applied to the wound twice daily for 8 weeks. The second group received a placebo ointment during the same period. The third group did not receive any treatment and served as the control group. Results The median (interquartile range=[Q1, Q3]) FTT was 1.35 (1.15, 1.62) mm, 1.00 (0.95, 1.02) mm, and 1.25 (0.8, 1.5) mm in the control, tamoxifen, and placebo groups, respectively (P=0.069). However, the FTT in the tamoxifen group was less than in the placebo and control groups. The median angiogenesis was 3.5 (3.00, 6.25), 8.00 (6.75, 9.25), and 7.00 (5.50, 8.25) vessels per high-power field for the control, tamoxifen, and placebo groups, respectively (P=0.067). However, the median angiogenesis was higher in the tamoxifen group than in the control group. No significant difference was observed in the mean SSA between the tamoxifen group and the control group (P=0.990). Conclusions Local application of tamoxifen increased angiogenesis and decreased the FTT, with no change in the SSA in burned skin areas. These effects are expected to expedite the wound healing process, reducing contracture and preventing hypertrophic scar and keloid formation.

Development of Vegetation Structure after Forest Fire in the East Coastal Region, Korea (동해안 산불 피해지에서 산불 후 경과 년 수에 따른 식생 구조의 발달)

  • 이규송;정연숙;김석철;신승숙;노찬호;박상덕
    • The Korean Journal of Ecology
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    • v.27 no.2
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    • pp.99-106
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    • 2004
  • We developed the estimation model for the vegetation developmental processes on the severely burned slope areas after forest fire in the east coastal region, Korea. And we calculated the vegetation indices as a useful parameter for the development of land management technique in the burned area and suggested the changes of the vegetation indices after forest fire. In order to estimate the woody standing biomass in the burned area, allometric equations of the 17 woody species regenerated by sprouter were investigated. According to the our results, twenty year after forest fire need for the development to the normal forest formed by 4 stratum structure, tree, sub-tree, shrub and herb layer. The height of top vegetation layer, basal area and standing biomass of woody species show a tendency to increase linearly, and the ground vegetation coverage and litter layer show a tendency to increase logarithmically after forest fire. Among vegetation indices, Ive and Ivcd show a tendency to increase logarithmically, and Hcl and Hcdl show a tendency to increase linearly after forest fire. The spatial variation of the most vegetation factors was observed in the developmental stages less than the first 5 years which were estimated secondary disaster by soil erosion after forest fire. Among vegetation indices, Ivc and Ivcd were the good indices for the representation of the spatial heterogeneity in the earlier developmental stages, and Hcl and Hcdl were the useful indices for the long-term estimation of the vegetation development after forest fire.

Effect of Prescribed Burning to Avian Community in Sihwa Grassland, Korea (시화호 초지대의 계획소각에 의한 조류군집의 영향)

  • Yoo, Seung-Hwa;Kang, Tae-Han;Paik, In-Hwan;Kim, Ho-Joon;Lee, Han-Soo;Kim, In-Kyu
    • Korean Journal of Environment and Ecology
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    • v.23 no.4
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    • pp.317-325
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    • 2009
  • This study was presented to effect of prescribed burning to the avian fauna and was conducted from March to October 2007 in Sihwa grassland, Gyeonggi-do, Korea. Prescribed burning was conducted at Sihwa grassland of Songjeong-ri Mado-myeon, Hwaseong city from 28th February to 1 st March 2007. Thirty birds species were observed and sum of the maximum count was 181 individuals at the prescribed burning area for all survey time. Observed species was 24 species and sum of the maximum count was 154 individuals on the unburned area. Number of species and sum of the maximum count at the prescribed burning area was greater than unburned area. There is no differences in the dominant species between prescribed and unburned area. Average number of species, number of individuals, species diversity and species richness of the prescribed burning area were greater than unburned area in early stage (from March to June) after prescribed burning. Community indices in burned area during early season were different with unburned area by prediscribed burning. However, the indices had became similar between burned and unburned area as time goes by. Disturbance by prescribed burning created new habitat and feeding site temporarily for the avian species in grassland. We would suggest that prescribed burning is most effective method to maintain grassland ecosystem from the invading bush or tree and periodical prescribed burning is a good method to preserve and manage the grassland ecosystem.

A Study on the Remodeling of Injeongjeon Area at Changdeokgung Palace in 1908 (1908년 창덕궁 인정전 일곽의 개조에 관한 연구)

  • Woo, Don-Son;Kee, Sehwang
    • Journal of architectural history
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    • v.23 no.2
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    • pp.53-64
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    • 2014
  • During the Joseon Dynasty, Injeongjeon area at Changdeokgung Palace was a core space in which major state affairs took place. Since founded in 1405, the Injeongjeon area's spatial composition has been changed while it was repeatedly burned down and rebuilt several times. However, despite many studies and researches on the Chandeokgung Palace and the Injeongjeon area, the changes of the area in the 20th century have not been examined thoroughly. This study attempts to find out the procedure and purposes of the remodeling of the Injeongjeon area in 1908. It is possible to presume that the motif of this remodeling construction, worked out by the Residency-General, was to transform the area similar to Ekkensho or Audience Hall area at Meiji Palace regarding the following facts: only Japaneses' participation in the construction, renaming the area as Alhyunso (Ekkensho), and involvement of Ito Hirobumi. Comparing plans of the remodeled Injeongjeon area at the Chandeokgung Palace with the Ekkensho area at the Meiji Palace, we can confirm this presumption and suggest the possibility that the Residency-General wanted to reduce the majesty and power of the Joseon Dynasty's Palace by this remodeling.

A cycle simulation of the S.I. engine and it's verification test (S.I. 엔진의 사이클 시뮬레이션 및 이의 확인 실험)

  • 목희수;김승수
    • Journal of the korean Society of Automotive Engineers
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    • v.10 no.6
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    • pp.72-84
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    • 1988
  • Engine performance is one of the main objectives specified at the beginning of a new engine design project. The cycle simulation for SI engine is based on the zero-dimensional gas exchange model and a heat release expression by Viebe. This program also requires minimum input data and takes only a short time to run. Heat transfer from cylinder transfer formula. The flow coefficient (effective area) is calculated from valve lift using the standard flow coefficient curve and engine friction is calculated from the Millington and Hartles' engine friction formula. The chemical species considered in burned gas are 6 species CO, CO, H$_{2}$, H$_{2}$O, $O_{2}$, N$_{2}$ and the cylinder pressure, homogeneous cylinder temperature, gas composition and burned fraction are calculated at each crank angle through the cycle. To check the validity and accuracy, experimental study was done with 3 engines for measuring cylinder pressure, indicated mean effective pressure, brake mean effective pressure and air flow rate, etc. Despite its simple assumptions, cycle simulation showes excellent breathing and performance correlation when compared with data of tested engines, and have been proved useful in engine design.

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