• Journal of Korea Water Resources Association
• /
• v.51 no.8
• /
• pp.729-737
• /
• 2018

This study investigates the sediment processes the Improved-pneumatic-movable weir through laboratory experiments considering changing channel slopes. Experimental results show that the delta migrates towards the weir and the delta height increases as time passes. Moreover, as the delta approaches the weir, the delta migration speed decreases. As the dimensionless delta location increases, the effective height of dimensionless delta and the dimensionless reservoir capacity increases. Therefore, under the same slope conditions, the sediment deposition volume of the delta is small as the channel slope is mild. This means that the channel slope affects the development of the delta in the upstream of the Improved-pneumatic-movable weir. At the beginning of the experiment, the foreset slope is mild. However, the foreset slope of the delta increases with water depth as the delta migrates downstream. Moreover, as the slope is mild, the ratio of delta front length to delta height is close to 1, and the dimensionless delta height and the dimensionless delta migration speed decrease. As the delta height increases, the water depth, the velocity approaching to the weir and the delta migration speed decrease.

• Journal of Coastal Disaster Prevention
• /
• v.1 no.1
• /
• pp.1-9
• /
• 2014

In order to examine the characteristics of tsunami run-up heights on impermeable/permeable slope, a numerical wave tank by upgrading LES-WASS-3D was used in this study. Then, the model were compared with existing hydraulic model test for its verification. The numerical results well reproduced experimental results of solitary wave deformation, propagation and run-up height under various conditions. Also, the numerical simulation with a slope boundary condition has been carried out to understand solitary wave run-up on impermeable/permeable slope. It is shown that the run-up heights on permeable slope is 52.64-63.2% smaller than those on the impermeable slope because of wave energy dissipation inside the porous media. In addition, it is revealed that the numerical results with slope boundary condition agreed well with experimental results in comparison with the results by using stair type boundary condition.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2000.10b
• /
• pp.60-64
• /
• 2000

This examination of vegetation is conducted from lune to Oct. 1999 through on the spot survey, centering on the habitat of Abies koreana around Imgeolryeong, langteomok, and Jeseokbong in Mt Jiri and Yeongsil path and Seongpanak path in Mt. Halla. Species composition tables of the Abies koreana community by altitude and slope in Mt. Jiri and Mt. Halla are made based on the community composition tables examined in quadrat. The Abies koreana-Saso quelpaertensis community in a west slope of Mt. Halla is found that Abies koreana of 4-6m in height forms subtree layer and that of 8-9m in height the tree layer and it reflects a difference between community structure by slope and main composition species. While the tree layer of Abies koreana community is 12-14 in height around the area of 1, 290-1, 560m above the sea of Imgeolryong and path from Baekmudong to Jangteomok, it is 8-12m in height in the area of 1, 680-1, 780m above the sea of path from Jangteomok to Jeseokbong. It means that community structure depends on area and attitude. This study finds out that commonly appearing composition species similar to coverage and presence are Lepisorus thunberianus, Quercus mongolica, Soidago virga-aurea var. asiatica, Ligularia fischeri, Carex lanceolata, Clintonia udensis, Magnolia sieboldii, Betula ermani, Acer Pseudo-sieboldianum, As soil environment of surveyed area, pH of surveyed spots is similar in Mt. Jiri and Mt. Halla, electrical conductvity is higher in Mt Jiri, and contents of organic matter is relatively higher in a west slope of Mt. Jiri and Mt. Halla and lower in their south and west slopes. Contents of organic matter and total nitrogen show that the area of 1, 550m above the sea in a west slope of Mt. Halla is some higher. For pH and contents of total nitrogen and organic matter, Mt. Halla is higher than Mt. Jiri but for electrical conductivity , Mt. Jiri is relatively higher than Mt. Halla.

• Plant Resources
• /
• v.3 no.2
• /
• pp.138-147
• /
• 2000

This examination of vegetation is conducted from June to Oct. 1999 through on the spot survey, centering on the habitat of Abies koreana around Imgeolryeong, Jangteomok, and Jeseokbong in Mt Jiri and Yeongsil path and Seongpanak path in Mt. Halla. Species composition tables of the Abies koreana community by altitude and slope in Mt. Jiri and Mt. Halla are made based on the community composition tables examined in quadrat. The Abies koreana-Saso quelpaertensis community in a west slope of Mt. Halla is found that Abies koreana of 4-6m in height forms subtree layer and that of 8-9m in height the tree layer and it reflects a difference between community structure by slope and main composition species. While the tree layer of Abies koreana community is 12-14 in height around the area of 1,290-1,560m above the sea of Imgeolryong and path from Baekmudong to Jangteomok, it is 8-12m in height in the area of 1,680-1,780m above the sea of path from Jangteomok to Jeseokbong. It means that community structure depends on area and attitude. This study finds out that commonly appearing composition species similar to coverage and presence are Lepisorus thunberianus, Quercus mongolica, Solidago virga-aurea var. asiatica, Ligularia fischeri, Carex lanceolata, Clintonia udensis, Magnolia sieboldii, Betula ermani, Acer pseudo-sieboldianum. As soil environment of surveyed area, pH of surveyed spots is similar in Mt. Jiri and Mt. Halla, electrical conductivity is higher in Mt Jiri, and contents of organic matter is relatively higher in a west slope of Mt. Jiri and Mt. Halla and lower in their south and west slopes. Contents of organic matter and total nitrogen show that the area of 1,550m above the sea in a west slope of Mt. Halla is some higher. For pH and contents of total nitrogen and organic matter, Mt. Halla is higher than Mt. Jiri but for electrical conductivity, Mt. Jiri is relatively higher than Mt. Halla.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.29 no.2
• /
• pp.114-117
• /
• 1984

To investigate a possibility of screening for the drought resistance of rice varieties in the slope-ridges, this experiment was conducted in Youngnam Crop Experiment Station in 1982. Seeds were vertically seeded on the slope-ridges which has 30 degree slopes from water level at the front to 1 meter height at the back side. A significant positive correlation was observed between the height of slope-ridges and the PF values (Y=2.25 +0.007 X, r =0.990${\ast}\;{\ast}$).The heading date delayed, the culm length was shortened and the yield was decreased in accordance with the height of slope-ridges. Based upon the above results, it was possible to read the drought resistance of the rice varieties tested. Samnambyeo, Milyang 26, Jinjubyeo and Nongrimna 1 were classified as the resistant ones, while Knob 361-1-8-6-149 was susceptible one.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.03a
• /
• pp.1264-1270
• /
• 2010

In this study, the effects of slope inclination and rainfall on weathered soil slope stability were investigated for current cut soil slope design criteria. A series of slope stability analysis was performed on the slopes with the same height (5m), but different inclinations (1:0.8, 1:1, 1:1.2, 1:1.5, 1:2). Seepage analysis was also conducted to examine the rainfall effects directly and compare the combined seepage and slope stability analysis results with the slope stability analysis results for rainy season from the current cut soil slope design criteria. Typical properties for weathered soils were used in both the slope and seepage analysis. The analysis results showed that, for the slopes much steeper than the standard slopes, the factor of safety criteria were satisfied. Therefore, it appears that the slope designs by current cut soil slope design criteria lead to conservative results.

• Journal of Environmental Impact Assessment
• /
• v.19 no.6
• /
• pp.527-537
• /
• 2010

This study are Geumjung mountain fortress of the Busan Metropolitan City in the north gate of the East gate around the trail to identify the vegetation structure importance value, dominance, species diversity, similarity index analysis. Results of the study, plot on the western slopes elevation 423-636m, slopes of $15{\sim}20^{\circ}$ slope areas, Pinus densiflora, Pinus thunbergii, Quercus acutissima, Pinus thunbergii, Pinus rigida, Carpinus coreana, Quercus mongolica are fulfilling a community. Trees layer a height 8~12m, coverage 40~70%, sub-trees layer the height 3~7m, coverage 10~80%, shrubs layer the height 0.8~1.5m, coverage 20-30%, herb layer the height 0.1~0.5m, coverage 5-10% were in the range of plot in the east slope elevation 452-647m, slopes in the slope of $5-30^{\circ}$ and Pinus rigida, Pinus thunbergii, Pinus densiflora, Quercus mongolica, Quercus dentata, Carpinus coreana is fulfilling a community. The trees layer height 8~13m, coverage 0~70%, sub-trees layer the height 2~6m, coverage 0~80%, shrubs layer the height 0.8~1.5m, coverage 20-40%, herb layer the height 0.1-0.5m, coverage 5-40% were in the range. The survey showed to be in relatively good vegetation, but in some areas of Pinus rigida, Quercus acutissima, as was predicted in succession, the shrub layer in the plot of some dominated vine plants and vegetation management will be needed for this purpose respectively.

• Journal of the Korean GEO-environmental Society
• /
• v.15 no.12
• /
• pp.53-59
• /
• 2014

In order to obtain basic data for reasonable design of rockfall prevention net unreasonably being designed according to experiences, this paper determined a standard cross section and analyzed the effects of parameters such as inclination and height of slope faces, rockfall weight, separation distance on rockfall behaviors such as bounce height, kinetic energy and passage rate. The weight of rockfall changed from 400 kg to 700 kg and then to 1,000 kg. With the height of 20 m as the standard, the test was conducted with the inclination at $63^{\circ}$ and $55^{\circ}$ which may affect rockfall behaviors. Analysis was made while changing the fall height of rockfall from 3 m to 15 m and then to 20 m, thereby analyzing and evaluating changes in maximal kinetic energy occurring in the base of slope. According to the analysis result, in designing a rockfall prevention wire net, a design considering various conditions including inclination of the slope, expected size or weight of rockfall, situation of the slope and the shape of rockfall, and rockfall trace is judged necessary beyond the current uniform application.

• Imaging Science in Dentistry
• /
• v.37 no.1
• /
• pp.19-26
• /
• 2007

Purpose : To examine whether the maxillofacial skeletal morphology correlates with the condylar position and the anatomic characteristics of articular eminence using measurements of lateral cephalometric radiographs and individualized sagittal temporomandibular joint (TMJ) tomographs. Materials and Methods : I compared measurements of 202 TMJs of 101 orthodontic patients of Kangnung National University Dental Hospital. 1 used Pearson's correlation for comparison of the measuring values in lateral cephalometric radiographs and individualized sagittal TMJ tomographs. Results : Large occlusal plane angle tendency showed decreased width of posterior eminence slope, decreased depth of articular fossa and decreased posterior slope angle of eminence. Large mandibular plane angle tendency showed decreased superior joint space, decreased depth of articular fossa and decreased posterior slope angle of eminence. Large genial angle tendency showed decreased depth of articular fossa, decreased posterior slope angle of eminence and anterior position of condylar head. Large anterior facial height and large posterior facial height tendency showed increased width of posterior slope of eminence, increased depth of articular fossa, increased posterior slope angle of eminence and posterior position of condylar head. Conclusion : Maxillofacial skeletal morphology has correlation with the anatomic characteristics of TMJ. Individualized sagittal TMJ tomographs can provide useful information for anatomical analysis of TMJ.

• Journal of the Korean Wood Science and Technology
• /
• v.21 no.3
• /
• pp.45-52
• /
• 1993

Surveyed results on the slope of grain and the twist of sawn lumber of Pinus koraiensis, Larix leptolepis, and Pinus densiflora were summarized as follows: 1. The slope of grain of Pinus koraiensis has a Z-grain in the stem axis. The slope of grain was found to be the lowest at near to the pith and then constantly increased. At the height of 0.2m from the base of stem. a cross section of 35 annual rings was found to have a repeatedly increasing and decreasing slope of grain and then constantly decreased. At the height of 1.2m to 7.2m from the base of stem, the slope of grain increased conspicuously until the 10th annual ring, after which it increased near to the bark with repeatedly increasing and decreasing trends. 2. Pinus densiflora has a S-grain in the stem axis. The lowest slope of grain was found at near to the pith, and the highest in the 10 to 35 annual rings from the pith. 3. Larix leptolepis has a S-grain. At the height of 3.2m from the base of stem, the big fluctuation of the slope of grain was found without any particular trend. 4. The slope of grain and the twist between natural and reforested timber of Pinus koraiensis were found to be almost the same trend in viewpoint of the annual ring. The maximum slope of grain of imported Siberian timber of Pinus koraiensis was found at the 10 annual rings, which was quite similar to that of native species in Korea, but the big difference of the twist was found at 140 annual rings. 5. The twist was little at the mature wood of reforested Pinus koraiensis and Siberians and the duplicated part of mature and juvenile woods of those. On the contrary, the twist was great at the duplicated part of mature and juvenile woods of Pinus koraiensis. 6. The twist of Larix leptolepis showed the S-direction which coincided with that of slope of grain. The twist was greatest at the part of juvenile wood and little at the duplicated part of mature and juvenile woods, and little difference of twist was found between mature and juvenile woods. 7. Siberian larix having a minimum slope of grain showed the lowest twist, and the twist at the duplicated part of mature and juvenile woods showed a middle level of both mature and juvenile woods' portions.