• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.438-445
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• 2020

The characteristics of forest environmental factors were analyzed using the quantification theory (I) for prediction of the suitable area of erosion control dams. The results indicated that sediment discharge in small forest catchments was significantly correlated with dredging passage (0.7495) and age class (0.6000). In contrast, area (0.3416), slope gradient (0.3207), rainfall (0.3160), altitude (0.2990) and soil type (0.2192) were poorly correlated. Following quantification theory (I), we developed a selection decision table for erosion control dams based on sediment discharge rate as class I (highly suitable site, greater than 2.2496), class II (suitable site, 1.1248~2.2495), and class III (poorly suited site, lower than 1.1247).

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.428-434
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• 2022

This study was conducted to derive the site index of forest productivity of Robinia pseudoacacia (honey plant) to characterize suitable planting sites and to investigate the effect of the site environmental factors on the site index using the quantification theory I method. The data used in the analysis were growth factors (stand age, dominant height, etc.) of the 6th national forest resources survey and various site environmental factors of a forest soil map (1:5,000). The average site index value of the R. pseudoacacia stand in Korea was 14 (range, 8 to 18). The environmental factors affecting the site index were parent rock, climatic zone, soil texture, local topography, and altitude. The accuracy of the estimation model using quantification theory I was only 33%. However, the correlation between the site index and the site environmental factors was statistically significant at the 1% level. Results of quantification analysis between site index and site environmental factors revealed that metamorphic and igneous rocks received high grades as parent rocks, climate zones received higher grades than central temperate zone, clay loam and silt loam received high grades in soil texture, and hillside received a high grade in local topography. Analysis of the partial correlation between site topographical factors and forest productivity (site index) found that soil class and altitude were partially correlated to x by 0.4129 and 0.4023, respectively, indicating that these factors are the most influential variables.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1470-1474
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• 2004

This paper addresses the development of inverse compensation techniques for a class of ferromagnetic transducers including magnetostrictive actuators. In this work, hysteresis is modeled through the domain wall theory originally proposed by Jiles and Atherton[1]. This model is based on the quantification of the energy required to translate domain walls pinned at inclusions in the material with the magnetization at a given field level specified through the solution of an ordinary differential equation. A complementary differential equation is then employed to compute the inverse which can be used to compensate for hysteresis and nonlinear dynamics in control design.

• Journal of Korean Society of Forest Science
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• v.110 no.1
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• pp.64-71
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• 2021

Recently, climate change has gradually accelerated the occurrence of landslides. Among the various effects caused by landslides,debris flow is recognized as particularly threatening because of its high speed and propagating distance. In this study, the impacts of various factors were analyzed using quantification theory(I) for the prediction of debris flow hazard soil volume in Seoraksan National Park, Korea. According to the range using the stepwise regression analysis, the order of impact factors was as follows: vertical slope (0.9676), cross slope (0.6876), altitude (0.2356), slope gradient (0.1590), and aspect (0.1364). The extent of the normalized score using the five-factor categories was 0 to 2.1864, with the median score being 1.0932. The prediction criteria for debris flow occurrence based on the normalized score were divided into four grades: class I, >1.6399; class II, 1.0932-1.6398; class III, 0.5466-1.0931; and class IV, <0.5465. Predictions of debris flow occurrence appeared to be relatively accurate (86.3%) for classes I and II. Therefore, the prediction criteria for debris flow will be useful for judging the dangerousness of slopes.

• Journal of Korean Society of Forest Science
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• v.97 no.3
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• pp.326-331
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• 2008

This study was carried out to analyze the characteristics of each factors by using the quantification theory(I) for prediction of landslide hazard area. The results obtained from this study were summarized as follows; The stepwise regression analysis between landslide sediment ($m^3$ ) and environmental factors, factors affecting landslide sediment ($m^3$ ) were high in order of mixed (forest type), < 15 cm(soil depth), 801~1,200 m (altitude), $31{\sim}40^{\circ}$ (slope gradient), 46 cm < (soil depth), 1,201 m < (altitude) and s(aspect). According to the range, it was shown in order of soil depth (0.3784), altitude (0.2876), forest type (0.2409), slope gradient (0.1728) and aspect (0.1681). The prediction of landslide hazard area was estimated by score table of each category. The extent of prediction score was 0 to 1.2478, and middle score was 0.6239. Class I was over 1.1720, class II was 0.7543 to 0.1719, class III was 0.4989 to 0.7542 and class IV was below 0.4988.

• Journal of Korean Society of Transportation
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• v.28 no.3
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• pp.51-57
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• 2010

In this study, damages due to the aircraft noise were examined in more than 190 elementary, middle and high schools near the airports in Korea, and the persecutory idea forecast model was established using the quantification theory type II. Via the survey of 1,012 teachers in the schools, a class interference forecast model was established, and the noise characteristics of five areas, four military/civil common-use airports and one shooting range, were examined. The following conclusions were made from the study. WECPNL values in the five military/civil common-use airports showed that all of them were Class 1 or 2 affected areas, which indicated that they had serious aircraft noise problems to be addressed. The most influential factor in the aircraft noise persecutory idea model was the distance between the airport and the school. It showed a positive relationship at a distance of less than 5 km, and a negative relationship at a distance of 10 km or more. The number and time of aircraft noise exposure as well as the types of airports and window structures had strong influences. The forecast model had a correlation ratio of 0.56, which indicates that it is highly appropriate. In the class interference factor analysis, the time and number of aircraft noise exposure were strong influential factors, and the results varied according to the service duration and sex of teachers. This model had a correlation ratio of 0.61, which indicates it is highly appropriate.

• Korean Journal of Environment and Ecology
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• v.20 no.4
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• pp.415-424
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• 2006

This study was carried out to analyze the characteristics of forest watershed factors by using the quantification theory(I) for evaluation and prediction of the failure hazard area. Present $sediment(m^3/yr/ha)$ of erosion control dams were investigated in 95 sites of erosion control dam constructed during 1986 to 1999 in Gyeongnam province. The results obtained from this study were summarized as follows; General condition of class I(Very hazard area) were as follow; Igneous rock in parent rock, coniferous in forest type, below 20year in stand age, below 30cm in soil depth, SCL in soil texture, $31{\sim}40%$ in gravel contents, $S{\sim}E$ in aspect, $2,501{\sim}3,600m$ in length of main stream, $26{\sim}30$ in number of total streams, $6,601{\sim}10,000m$ in length of total streams, over 3 in stream order, over 16 in number of first streams order and over $31^{\circ}$ of slope gradient. General condition of class IIl(hazard area) were as follow; Metamorphic rock in parent rock, hardwood in forest type, over $21{\sim}24year$ in stand age, $31{\sim}40cm$ in soil depth, SiCL or SCL in soil texture, $11{\sim}20%$ in gravel contents, $S{\sim}W$ in aspect, $1,501{\sim}2,600m$ in length of main stream, $6{\sim}10$ in number of total streams, $3,501{\sim}5,500m$ in length of total streams, 2 in stream order, $6{\sim}10$ in number of first streams order and over $31^{\circ}$ of slope gradient. General condition of class III(Un hazard area) were as follow; Sedimentary rock in parent rock, mixed in forest type, over 25year in stand age, $41{\sim}50cm$ in soil depth, SiCL in soil texture, below 10% in gravel contents, $N{\sim}W$ in aspect, below 500m in length of main stream, below 5 in number of total streams, below 1,000m in length of total treams, below 1 in stream order, below 2 in number of first streams order and below $25^{\circ}$ of slope gradient. The prediction method of suitable for failure hazard area divided into class I, II, and III for the convenience of use. The score of class I evaluated as a very hazard area was over 4.8052. A score of class II was 4.8051 to 2.5602, it was evaluated as a hazard area, and class III was below 2.5601, it was evaluated as a un hazard area.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.4
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• pp.1-11
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• 2001

This study was carried out to analyze the characteristics of forest environmental and stream morphological factors by using the quantification theory(I) for evaluation of the watershed stability. Present annual mean sediment yield of erosion control dams were investigated in 167 sites of erosion control dam constructed during 1986 to 1999 in Gyeongbuk. The results obtained from this study were summarized as follows; According to the coefficients of partial correlation, each factor affecting to sediment was shown in order of gravel contents, number of first streams order, number of total streams, length of total streams, forest type, length of main stream, parent rock, stand age, soil texture, stream order, slope gradient, soil depth and aspect. Descriptions of class I were as follow; Igneous rock of parent rock, hardwood stands of forest type, less than 20 year of stand age, less than 30cm of soil depth, sandy clay loam of soil texture, more than 41% of gravel contents, south~east of aspect, 2,501~3,500m of length of main stream, 21~25 of number of total streams, 5,501~10,000m of length of total streams, 3 or more than 4 of stream order, more than 16 of number of first stream orders and more than $31^{\circ}$ of slope gradient. Descriptions of class II were as follow; Metamorphic rock of parent rock, coniferous stands of forest type, more than 25 year of stand age, 31~40cm of soil depth, silt loam of soil texture, 11~20% of gravel contents, north~west of aspect, 2,501~3,500m of length of main stream, 16~20 of number of total streams, 3,501~5,500m of length of total streams, 3 of stream order, 11~15 of number of first stream orders and more than $31^{\circ}$ of slope gradient. Descriptions of class III were as follow; Sedimentary rock of parent rock, mixed stands of forest type, more than 25 year of stand age, more than 51cm of soil depth, silty clay loam of soil texture, less than 10% of gravel contents, south~west of aspect, less than 500m of length of main stream, less than 5 of number of total streams, less than 1,000m of length of total streams, less than 1 of stream order, less than 2 of number of first stream orders and less than $25^{\circ}$ of slope gradient. The prediction method of suitable site for erosion control dam divided into class I, II, and III for the convenience of use. The score of class I evaluated as a very unstable area was more than 8.4494. A score of class II was 8.4493 to 6.0452, it was evaluated as a moderate stable area, and class III was less than 6.0541, it was evaluated as a very stable area.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.233-239
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• 2014

This study was carried out to propose the criteria for the prediction of landslide occurrence through analysis the influence of each factor by using the quantification theory. The results obtained from this study are summarized as follows. From a stepwise regression analysis between the landslide area($m^2$) and environmental factors, the factors strongly affecting the landslide sediment($m^2$) were the Parents rock (igneous), cross slope(complex), coniferous forests (forest type) and slope gradient ($21{\sim}30^{\circ}$). According to the range, it was shown in order of Cross slope (0.2922), Parents rock (0.2691), Forest type (0.2631) and Slope gradient (0.2312). The range of prediction score of landslide occurrence has been distributed between score 0 and score 1.0556, the median value was score 0.5278. The prediction for class I was over 0.7818, for class II was 0.5279 to 0.7917, for class III 0.2694 to 0.5278 and for class IV was below 0.2693. The prediction on landslide occurrence appeared relatively high accuracy rate as 72% for class I and II. Therefore, this score table for landslide will be very useful for judgement of dangerous slope.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.173-185
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• 2015

This study aims to investigate the characteristics and types of car accidents and establish a prediction model by analyzing 456 car accidents having occurred in the 11 tunnels in Busan, through statistical analysis techniques. The results of this study can be summarized as below. As a result of analyzing the characteristics of car accidents, it was found that 64.9% of all the car accidents took place in the tunnels between 08:00 and 18:00, which was higher than 45.8 to 46.1% of the car accidents in common roads. As a result of analyzing the types of car accidents, the car-to-car accident type was the majority, and the sole-car accident type in the tunnels was relatively high, compared to that in common roads. Besides, people at the age between 21 and 40 were most involved in car accidents, and in the vehicle type of the first party to car accidents, trucks showed a high proportion, and in the cloud cover, rainy days or cloudy days showed a high proportion unlike clear days. As a result of analyzing the principal components of car accident influence factors, it was found that the first principal components were road, tunnel structure and traffic flow-related factors, the second principal components lighting facility and road structure-related factors, the third principal factors stand-by and lighting facility-related factors, the fourth principal components human and time series-related factors, the fifth principal components human-related factors, the sixth principal components vehicle and traffic flow-related factors, and the seventh principal components meteorological factors. As a result of classifying car accident spots, there were 5 optimized groups classified, and as a result of analyzing each group based on Quantification Theory Type I, it was found that the first group showed low explanation power for the prediction model, while the fourth group showed a middle explanation power and the second, third and fifth groups showed high explanation power for the prediction model. Out of all the items(principal components) over 0.2(a weak correlation) in the partial correlation coefficient absolute value of the prediction model, this study analyzed variables including road environment variables. As a result, main examination items were summarized as proper traffic flow processing, cross-section composition(the width of a road), tunnel structure(the length of a tunnel), the lineal of a road, ventilation facilities and lighting facilities.