• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.23-36
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• 2012

This study aims to think about the problem of dolmens: the reasons for the presence of dolmens and how to construct it, at the point of view of geographical and geomorphological. The subjects of this study is the dolmens which locate between at Dogok Hyosanri and Chunyang Daesinri Hwasoon-gun, Jeonlanamdo. The study areas in Hyosanri, Daesinri has been observed as follows. First, the long axis direction of Dolmen upper stone and the slope one are the same. Second, tor, block stream, hockey stick, etc. Third, Composition of the soil silt> sand> clay is distributed in the order. Forth, The soil of high quality silt and the roundness of angular, sub-angular-level and the high frequency, peaks of quarts and illite clay minerals show. Fifth, in the result of $SiO_2/Al_2O_3$, $SiO_2/R_2O_3$, and CIA(Chemical Index of Alteration), Hyosanri, Daesinri areas show mechanical weathering was dominant and chemical weathering environment was not being progressed. The blocks used in construction of dolmens had moved to the bottom of slopes by mass movement such as solifluction then them which had been placed in the position seem to be used by people of Bronze. Based on the above results, the process of construction of dolmens can be estimated as follows. They would dig up the ground under the upper stone of dolmens, put the supporting stone in the place, then dig up earth, place into remains, close the obturating stones, then heal up earth.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.437-440
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• 2008

This study enforced to produce the planting concrete block which could be applied to various slopes economically. First of all, the physical properties was investigated with the various types of aggregate and aggregate ratio of the paste for the lead to mixture proportion of the planting concrete. As a result, the orchid stone as aggregate and 30% of aggregate ratio of the paste were used as the basic mixture proportion considering 20${\sim}$30% of maintained void ratio for the growth of plant, over 20% of capillary suction for holding water, and 3MPa as the minimum strength. For the result of the test to the new planting block which was quite different from existing planting concrete block, it could complement the problems and be possible to produce effectively and economically because various slopes like $40^{\circ}{\sim}75^{\circ}$, continual produce by extrusion, and pumping out were possible were possible.

• 유체기계공업학회:학술대회논문집
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• 1998.12a
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• pp.42-48
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• 1998

Numerical study is presented for the analysis of three-dimensional incompressible turbulent flows in multiblade centrifugal fan. Reynolds-averaged Navier-Stokes equations with standard k - $\epsilon$ turbulence model are transformed to non-orthogonal curvilinear coordinates, and are discretized with finite volume approximations. Linear Upwind Differencing Scheme(LUDS) is used to approximate the convection terms in the governing equations. SIMPLEC algorithm is used as a velocity-pressure correction procedure. The computational area is divided into three blocks; core, impeller and scroll, which are linked by multi-block method. The flow inside of the fan is regarded as steady flow, and mathematical formula established from the cascade theory and empirical coefficient are employed to simulate tile flow through the impeller. From comparisons between the computational results and the experimental data, the validity of the mathematical formula for the blade forces was examined and good results were obtained qualitatively. Hence, we can get the flow characteristics of multi-blade centrifugal fan and it will be a corner stone of the development of the multiblade centrifugal fan.

• The Journal of Engineering Geology
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• v.7 no.1
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• pp.37-52
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• 1997

This paper discribes the practical application of stability analysis on the revetment structures, and four different sections of revetment structures are considered in this study. As a result of stability analysis, the the section of inclined revetment with T.T.P. block shows the highest safety factor against to the sliding failure of cap concrete block, while the section of inclined revetment with rubble stone shows the highest safety factor against to the straight and circular sliding failure. And the safety factors are increased by increasing of the rigidity of covered materials and by decreasing of the slope angle. For the safety factor of overturnning and bearing capacity, the section of inclined revetment structures shows higher safety factors than the section of vertical structures, and the safety factors are increased by decreasing of the slope angle and by increasing of the bottom width of the structures.

• Journal of architectural history
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• v.4 no.1
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• pp.71-78
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• 1995

This study aims 1) to estimate the form of living house of pre-urbanization of Inchon, and 2) to ensure originality of to be achieve urban plan and living space plan which is base on local character by 3) arranging changed character of living space through the urbanization sequence by invest of house in natural village at Pupyung. The character of arranging living space of house at Pupyung is placing Sarang-chae(husband's block of house) instead of making another Haenrang-chae (visitor's block of house) and Sarang-chae is attach importance to Man's living space but today, have disappearing the uses of Sarang-bang (husband's living space) because by Man lives An-bang(originally woman's space). The character of plan is arranging room in both side of Maru(wooden living floor) in spite of different structure, and the uses of plan or room is changing to fit to purpose of according to environment of living. Generally, the structure is made by natural stone and cubed column, and used smaller member cause by rare wood material.

• Journal of the Korean association of regional geographers
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• v.10 no.1
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• pp.53-66
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• 2004

There are various granite landforms including block stream(natural monument No. 435) within Mt. Biseul, in Daegu city. The Daegyunsa(temple) and community of rhododendron around the summit of the mountain provide visitors many objects o( interest in cultural & ecological heritage. This paper aimed to develope nature trails of various type according to visitor's characteristics. 1) Various granite landforms develope along with the main path up the mountain(block stream-gnamma-exfoliation-poligonal cracking-talus-core stone-sheeting joint-tor-free face-high flat summit). 2) The explanatory note on terminology, origin, characteristics of geomorphic resources are developed in this paper for the first time. 3) In Consideration of the path line of flow of visitor, the best field study sites and the most effective nature trails are designed for visitor. 4) Three nature tails are designed for visitor according to the type and the length of visitor's stay.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.3 s.116
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• pp.12-22
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• 2006

The purpose of this study is to evaluate visual preferences of the methods for river embankment based on seasonal changes and to reveal the relationship between visual preference and effective factors, which are the physical and esthetic elements inside the river. For this research seven river embankment methods including concrete block, concrete wall, gabion, and vegetated concrete block were selected in Dongchon of Gwangyang. Twenty-eight pictures by the four pictures of each embankment method based on seasonal changes, the winter and summer of the first and second years after construction were used for a photo-questionnaire by 49 participants. In the analysis of the relationship between visual preference and effective factors, the independent variables included eight factors: form of the material, harmony with the surroundings, the cleanness of river floor, the green area of embankment methods, the water area in river floor, the stone and sand area in river floor, the planting area in river floor, and the area of embankment itself. The result of this study are as follows. First, visual preference in summer was higher than in winter, and the summer landscape of the second you scored the highest value for visual preference. Second, similarly to the way the vegetated concrete block produced a green effect, cobblestone and gabion embankments made of natural materials scored higher than others, whereas the concrete retaining wall scored the lowest of all methods because of it's artificiality. Third, the seven independent variables, except form of the material, are proved statistically significant at the 5% level. The water area in river floor, harmony with the surroundings, the planting area in river floor, and the cleanness of the river floor were revealed as more effective factors influencing visual preference. The research results suggest that the riverscape has to be controlled in terms of seasonal change and embankment methods. Natural materials and green effects in embankment methods are more important for increasing landscape preference, and the landscape factors inside a river should also be considered important variables. It is recommended that advanced study on other factors affecting visual preference of the riverscape be carried out to support this research.

• Journal of Korean Society of Disaster and Security
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• v.16 no.4
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• pp.9-18
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• 2023

Climate change affects the safety of river revetments, especially those associated with external flooding. Research on slope reinforcement has been actively conducted to enhance revetment safety. Recently, technologies for producing embankment blocks using recycled materials have been developed. However, it is essential to analyze the impact of block shapes on the flow characteristics of exclusion zones for revetment safety. Therefore, this study investigates the influence of revetment block shapes on the hydraulic characteristics of revetment surfaces through 3D numerical simulations. Three block shapes were proposed, and numerical analyses were performed by installing the blocks in an idealized river channel. FLOW-3D was used for the 3D numerical simulations, and the variations in maximum flow velocity, bed velocity beneath the revetment, and maximum shear stress were analyzed based on the shapes of the revetment blocks. The results indicate that for irregularly sized and spaced revetment blocks, such as the natural stone-type vegetation block (Block A), when connected to the revetment in an irregular manner, the changes in flow velocity in the revetment installation zone are more significant than those for Blocks B and C. It is anticipated that considering the topographical characteristics of rivers in the future will enable the design of revetment blocks with practical applicability in the field.

• Journal of Korean Society for Geospatial Information Science
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• v.11 no.1 s.24
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• pp.45-49
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• 2003

This study was peformed in two ways, which are 'Before' 'After' carrying out trench search through GPR which is called 'Non Destructive Geophysical' to the expected area where the remains of historic interest could be distributed within the highway construction site from Dae-gu to Busan. As a result, the layer containing gravel and sand has more irregular specular surface then others containing silt and clay, And, apart block irregular specular surfaces of prominence and depression patter appeared. After performing trench search, verified that the site yield dolmens and lots of stone implements.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.443-445
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• 2008

Determination of allowable overtopping rate for coastal structure is a key point to determine the application of background of coastal structure while considering safety and economic efficiency. Thus, the accurate estimation of overtopping rate against coastal structure is essential. In general, estimation of overtopping against the coastal structure is based on an empirical formula or hydraulic experiment. In this study, we investigate the behavior of overtopping for rubble mound coastal structure with rubble armor stone and wave dissipating block using hydraulics experiment, and domestic or foreign design standard.