• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.359-366
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• 2011

The objective of this study was to analyze the changes of crown fire hazard possibility from the effects of forest tending works (FTW) in Pinus densiflora stands in Korea. The study sites were located in Youngju (FTW) and Bonghwa (Control) areas. Ten representative sample trees were destructively felled at each areas to analyze the crown fuel characteristics. The results of this study showed that crown fuel moisture content in Youngju and Bonghwa areas were 103.6% and 104.4%, respectively. The needles and twigs with less than 1cm diameter accounted 50.3% of the total crown fuel load in Youngju area and 62.0% in Bonghwa area. On the other hand, it was observed in Youngju that the canopy bulk density was $0.11kg/m^3$ lower but have 1.3 m higher average canopy base height therefore having a possibility of lower crown fire hazard as compared to Bonghwa that had higher canopy bulk density and lower canopy base height.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.305-310
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• 1997

There are many parameters in prediction of forest fire spread. The variables such as fuel moisture, fuel loading, wind velocity, wind direction, relative humidity, slope, and solar aspect have important effects on fire. Particularly, wind and slope factors are considered to be the most important parameters in propagation of forest fire. Generally, slope effect cause different wind distribution in mountain area. However, this effect is disregarded in complex geometry. In this paper, wind is estimated by applying computational fluid dynamics to the forest geometry. Wind velocity data is obtained by using CFD code with Newtonian model and slope is calculated with geometrical data. These data are applied fer 2-dimentional forest fire spreading algorithm with Korean ROS(Rate Of Spread). Finally, the comparison between the simulation and the real forest fire is made. The algorithm spread of forest fire will help fire fighter to get the basic data far fire suppression and the prediction to behavior of forest fire.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.434-437
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• 2008

In this study, we developed a fuel moisture variation prediction model on each day after precipitation during a spring forest fire exhibition period. For this research, we selected plots in pine forest on Sam-Chuck si and Dong-hae si in Kangwon do according to a forest density(low, mediate, high) and classified a surface woody fuel by a diameter.(below 0.6cm, $0.6{\sim}3cm$, $3{\sim}6cm$, and above 6cm). A validity of this model was verified by applying a fuel moisture variation after precipitation in this spring. In the result, $R^2$ was $0.76{\sim}0.92$. This model will be a useful for improvement of a forest fire danger rate forcast through a prediction a fule moisture in forest.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2019.08a
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• pp.122-123
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• 2019

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.217-222
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• 2007

Since 1973, we attain a successful achievement of nation-wide afforestation such as a thick forest and heaped-up leaves. However, the higher of the formation density in forest, the more dangerous to be a large-scale forest fire whenever fire occurs. According to the type of forest in the country, 42% of the forest is occupied by conifer forest that are highly flammable, and the distribution of forest age is in a transition period from immature forest to mature one. And the structure is too weak to the forest fire for the occurrence and spread because there are too many scrub and shrub trees in the forest. As a matter of course, it is on the increase of the thinning-forest that can shift the forest structure from a weak on forest fire to a strong one nowaday. In other words, thinning-forest has primary purposes such as the promotion of producing forest trees, production of excellent timbers, and build-up of public forest area. Furthermore, in some reports, the reduction of ladder fuel by eliminating the vertical/horizontal fuel in a forest and ensuring spaces in the forest can decrease the occurrence of forest fire and the risk of spread of burning as by-effect. Therefore, this study is designed to clarify the relation with the risk of forest fire by an on-spat-investigation of the characteristics of forest composition on the thinning and the non-thinning area.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2015.08a
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• pp.121-125
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• 2015

• Journal of Forest and Environmental Science
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• v.30 no.4
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• pp.362-369
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• 2014

This study investigated physical properties and combustion gas characteristics for 8 types of wood pellets (4 domestic and 4 imported products) distributed in the domestic market. Results showed that most pellet types were first-grade pellets in the wood pellet quality standards in Korea with the exception of 3 pellet types from K company (second-grade in mechanical durability), G company (off-grade in nitrogen content) and P company (second-grade in ash percentage). Mixed pellets which contained more lignin and sap content were higher in mechanical durability (%) than that of white pellets. From the combustion gas analysis results, NOx emitted from all pellets combustion was at acceptable levels for national emission standard of the Clean Air Conservation Act except for pellets from G company. In addition, CO levels from all types of wood pellets were acceptable except for pellets from D company and domestic pellets were higher CO levels than imported pellets. These results indicate the higher CO levels in domestic pellets due to the usage of forest thinning materials including logging debris which usually had the high content of bark.

• Journal of Energy Engineering
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• v.23 no.1
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• pp.7-20
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• 2014

The optimal woodchip production system was developed and the production cost of a forest woodchip fuel was calculated for utilizing the pitch pine, which covers around 480,000ha nationwide. the marginal price of the woodchip fuel considering the factor of supply price, electricity and heat selling price as well as capacity factor were suggested and the economic sensitivity analysis was conducted for various scenario. The most important variable which determine economic feasibility was a fuel cost for the power generation facility. If the electricity price is higher than the current SMP(System Marginal Price) or the capacity factor is higher than 80%, there fully is a benefit to consume the woodchip fuels produced in the suggested production system in this study. In addition, the additional benefit becomes more obvious when considering REC(Renewable Energy Certificate) and CDM(Clean Development Mechanism). Therefore, it is strongly suggested for domestic power generation sector to utilize the forest biomass fuel to achieve the obligatory target of RPS.

• Journal of Korean Society of Forest Science
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• v.104 no.1
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• pp.104-110
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• 2015

The objective of this study was to develop allometric equations for the estimation of crown fuel biomass of Pinus koraiensis in Korea. A total of twenty four representative sample trees were destructively sampled in Gapyeong, Hongcheon, and Jeongseon. Crown fuels were weighed separately for each fuel category by size class and by living and dead. The results of this study showed that the needles contributed the largest biomass (16.6 kg, 34.7%), followed by live branches with size ranging from 2~4 cm (9.0 kg, 18.9%), 1~2 cm (6.6 kg, 13.8%), <0.5 cm (5.1 kg, 10.6%), 0.5~1 cm (4.9 kg, 10.3%), and dead branches (3.2 kg, 6.8%), while the live branches with 4 cm (2.4 kg, 4.9%) as the lowest. The adjusted coefficient of determination values were the highest ($R^2_{adj}=0.6021{\sim}9742$) and standard error of estimate were the lowest (S.E.E.=0.2018~0.7271) in allometric equation $lnWt={\beta}_0+{\beta}_1lnD$. The available fuels that are consumed during crown fires (i.e., needles and twigs with diameter less than 1 cm) comprised 55.6% of the total crown fuel biomass.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.1
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• pp.1-12
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• 2014

Crown fire, the main propagation type of large forest fire, has caused extreme damage with the fast spread rate and the high flame intensity. In this paper, we developed the probability equation to predict the crown fires using the spatial features of topography, fuel and weather in damaged area by crown fire. Eighteen variables were collected and then classified by burn severity utilizing geographic information system and remote sensing. Crown fire ratio and logistic regression model were used to select related variables and to estimate the weights for the classes of each variables. As a results, elevation, forest type, elevation relief ratio, folded aspect, plan curvature and solar insolation were related to the crown fire propagation. The crown fire propagation probability equation may can be applied to the priority setting of fuel treatment and suppression resources allocation for forest fire.