• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.6
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• pp.357-366
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• 2021

In this study, hydraulic model tests were performed to investigate the stability of armor units at harbor side slope for rubble mound structures. The Korean design standard for harbor and fishery port suggested the design figures that showed the ratio of the armor weight for each location of rubble mound structures and it could be known that the same weight ratio was needed to the sea side and harbor side (within 0.5H from the minimum design water level) slope of rubble mound structures. The super structures were commonly applied to the design process of rubble mound structures in Korea and the investigation of the effects of super structures would be needed. The stability number (N_od = 0.5) was applied (van der Meer, 1999) and it showed that the armor (tetrapod) weight ratio for harbor side slope of rubble mound structures needed 0.8 times of that for sea side slope.

• Journal of Biosystems Engineering
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• v.3 no.2
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• pp.35-61
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• 1978

To find out the power tiller's travel and tractive characteristics on the general slope land, the tractive p:nver transmitting system was divided into the internal an,~ external power transmission systems. The performance of power tiller's engine which is the initial unit of internal transmission system was tested. In addition, the mathematical model for the tractive force of driving wheel which is the initial unit of external transmission system, was derived by energy and force balance. An analytical solution of performed for tractive forces was determined by use of the model through the digital computer programme. To justify the reliability of the theoretical value, the draft force was measured by the strain gauge system on the general slope land and compared with theoretical values. The results of the analytical and experimental performance of power tiller on the field may be summarized as follows; (1) The mathematical equation of rolIing resistance was derived as $$Rh=\frac {W_z-AC \[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\] sin\theta_1}} {tan\phi \[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]+\frac{tan\theta_1}{1}$$ and angle of rolling resistance as $$\theta _1 - tan^1\[ \frac {2T(AcrS_0 - T)+\sqrt (T-AcrS_0)^2(2T)^2-4(T^2-W_2^2r^2)\times (T-AcrS_0)^2 W_z^2r^2S_0^2tan^2\phi} {2(T^2-W_z^2r^2)S_0tan\phi}\] $$and the equation of frft force was derived as$$P=(AC+Rtan\phi)\[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]cos\phi_1 \ulcorner \frac {W_z \ulcorner{AC\[ [1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]sin\phi_1 {tan\phi[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\]+ \frac {tan\phi_1} { 1} \ulcorner W_1sin\alpha $$The slip coefficient K in these equations was fitted to approximately 1. 5 on the level lands and 2 on the slope land. (2) The coefficient of rolling resistance Rn was increased with increasing slip percent 5 and did not influenced by the angle of slope land. The angle of rolling resistance Ol was increasing sinkage Z of driving wheel. The value of Ol was found to be within the limits of Ol =2\ulcorner "'16\ulcorner. (3) The vertical weight transfered to power tiller on general slope land can be estim ated by use of th~ derived equation: $$R_pz= \frac {\sum_{i=1}^{4}{W_i}} {l_T} { (l_T-l) cos\alpha cos\beta \ulcorner \bar(h) sin \alpha - W_1 cos\alpha cos\beta$$The vertical transfer weight $R_pz$ was decreased with increasing the angle of slope land. The ratio of weight difference of right and left driving wheel on slop eland,$\lambda= \frac { {W_L_Z} - {W_R_Z}} {W_Z} $, was increased from ,$\lambda$=0 to$\lambda$=0.4 with increasing the angle of side slope land ($\beta = 0^\circ~20^\circ) (4) In case of no draft resistance, the difference between the travelling velocities on the level and the slope land was very small to give 0.5m/sec, in which the travelling velocity on the general slope land was decreased in curvilinear trend as the draft load increased. The decreasing rate of travelling velocity by the increase of side slope angle was less than that by the increase of hill slope angle a, (5) Rate of side slip by the side slope angle was defined as $ S_r=\frac {S_s}{l_s} \times$ 100( %), and the rate of side slip of the low travelling velocity was larger than that of the high travelling velocity. (6) Draft forces of power tiller did not affect by the angular velocity of driving wheel, and maximum draft coefficient occurred at slip percent of S=60% and the maximum draft power efficiency occurred at slip percent of S=30%. The maximum draft coefficient occurred at slip percent of S=60% on the side slope land, and the draft coefficent was nearly constant regardless of the side slope angle on the hill slope land. The maximum draft coefficient occurred at slip perecent of S=65% and it was decreased with increasing hill slope angle $\alpha$. The maximum draft power efficiency occurred at S=30 % on the general slope land. Therefore, it would be reasonable to have the draft operation at slip percent of S=30% on the general slope land. (7) The portions of the power supplied by the engine of the power tiller which were used as the source of draft power were 46.7% on the concrete road, 26.7% on the level land, and 13~20%; on the general slope land ($\alpha = O~ 15^\circ ,\beta = 0 ~ 10^\circ$) , respectively. Therefore, it may be desirable to develope the new mechanism of the external pO'wer transmitting system for the general slope land to improved its performance.l slope land to improved its performance.

• Journal of Biosystems Engineering
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• v.3 no.2
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• pp.34-34
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• 1978

To find out the power tiller's travel and tractive characteristics on the general slope land, the tractive p:nver transmitting system was divided into the internal an,~ external power transmission systems. The performance of power tiller's engine which is the initial unit of internal transmission system was tested. In addition, the mathematical model for the tractive force of driving wheel which is the initial unit of external transmission system, was derived by energy and force balance. An analytical solution of performed for tractive forces was determined by use of the model through the digital computer programme. To justify the reliability of the theoretical value, the draft force was measured by the strain gauge system on the general slope land and compared with theoretical values. The results of the analytical and experimental performance of power tiller on the field may be summarized as follows; (1) The mathematical equation of rolIing resistance was derived as $$Rh=\frac {W_z-AC \[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\] sin\theta_1}} {tan\phi \[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]+\frac{tan\theta_1}{1}$$ and angle of rolling resistance as $$\theta _1 - tan^1\[ \frac {2T(AcrS_0 - T)+\sqrt (T-AcrS_0)^2(2T)^2-4(T^2-W_2^2r^2)\times (T-AcrS_0)^2 W_z^2r^2S_0^2tan^2\phi} {2(T^2-W_z^2r^2)S_0tan\phi}\] $$and the equation of frft force was derived as$$P=(AC+Rtan\phi)\[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]cos\phi_1 ? \frac {W_z ?{AC\[ [1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\)\]sin\phi_1 {tan\phi[1+ \frac{sl}{K} \(\varrho ^{-\frac{sl}{K}-1\]+ \frac {tan\phi_1} { 1} ? W_1sin\alpha $$The slip coefficient K in these equations was fitted to approximately 1. 5 on the level lands and 2 on the slope land. (2) The coefficient of rolling resistance Rn was increased with increasing slip percent 5 and did not influenced by the angle of slope land. The angle of rolling resistance Ol was increasing sinkage Z of driving wheel. The value of Ol was found to be within the limits of Ol =2? "'16?. (3) The vertical weight transfered to power tiller on general slope land can be estim ated by use of th~ derived equation: $$R_pz= \frac {\sum_{i=1}^{4}{W_i}} {l_T} { (l_T-l) cos\alpha cos\beta ? \bar(h) sin \alpha - W_1 cos\alpha cos\beta$$The vertical transfer weight $R_pz$ was decreased with increasing the angle of slope land. The ratio of weight difference of right and left driving wheel on slop eland,$\lambda= \frac { {W_L_Z} - {W_R_Z}} {W_Z} $, was increased from ,$\lambda$=0 to$\lambda$=0.4 with increasing the angle of side slope land ($\beta = 0^\circ~20^\circ) (4) In case of no draft resistance, the difference between the travelling velocities on the level and the slope land was very small to give 0.5m/sec, in which the travelling velocity on the general slope land was decreased in curvilinear trend as the draft load increased. The decreasing rate of travelling velocity by the increase of side slope angle was less than that by the increase of hill slope angle a, (5) Rate of side slip by the side slope angle was defined as $ S_r=\frac {S_s}{l_s} \times$ 100( %), and the rate of side slip of the low travelling velocity was larger than that of the high travelling velocity. (6) Draft forces of power tiller did not affect by the angular velocity of driving wheel, and maximum draft coefficient occurred at slip percent of S=60% and the maximum draft power efficiency occurred at slip percent of S=30%. The maximum draft coefficient occurred at slip percent of S=60% on the side slope land, and the draft coefficent was nearly constant regardless of the side slope angle on the hill slope land. The maximum draft coefficient occurred at slip perecent of S=65% and it was decreased with increasing hill slope angle $\alpha$. The maximum draft power efficiency occurred at S=30 % on the general slope land. Therefore, it would be reasonable to have the draft operation at slip percent of S=30% on the general slope land. (7) The portions of the power supplied by the engine of the power tiller which were used as the source of draft power were 46.7% on the concrete road, 26.7% on the level land, and 13~20%; on the general slope land ($\alpha = O~ 15^\circ ,\beta = 0 ~ 10^\circ$) , respectively. Therefore, it may be desirable to develope the new mechanism of the external pO'wer transmitting system for the general slope land to improved its performance.

• Journal of Korea Water Resources Association
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• v.49 no.11
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• pp.941-949
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• 2016

The flow characteristics of the broad-crested side weir considering the levee's side slope of main channel ($ES_{ch}$) was investigated through hydraulic experiment in order to estimate the discharge coefficient equation. For applicability to actual river, levee's side slope of main channel 1:0.5, 1:1 and 1:2 were selected. Experimental results show that the new estimated equation for the discharge coefficient including $ES_{ch}$ is reasonable and effective in actual applications by comparing estimated and measured discharge over side weirs. Through a multiple linear regression analysis the importance of variabes were ordered as $ES_{ch}$ > $h/y_u$ > $L/y_u$ > $Fr_u$. Especially the discharge coefficient equation without $Fr_u$ was suggested, and the high applicability was reviewed by comparing the measured and calculated overflow of broad-chested side weir.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.529-536
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• 2003

In domestic case occurrence of cut slopes according to construction and expansion of road is necessary more than 70% of country has been consisted of mountain area. In the case of Kang-won Do, there are much mountains locals in road wiping away a disgrace and expanded and slant is connoting collapse danger of incision side by each kind calamity being urgent. When route alteration enforces disadvantageous road extension, stability examination and processing way about large slope happened are serious. During road extension work in the Kang-won DO secure stability for falling rock of road slope and failure that happen and established suitable reinforcement and countermeasure in reply in necessity. The Slope is divided rock slope and soil slope, and then in order to analysis soil slope apply LEM theory. And rock slope examined stability about stereographic projection and wedge failure. Is going to utilize in reinforcement and failure prevention if it is efficient cutting as reinterpreting stability and secure stability and wish to consider effective and robust processing plan of great principle earth and sand side, and present countermeasure inside with these data hereafter applying suitable reinforcement countermeasure about unstable section.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.493-498
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• 2003

In case of slope failure by planted protection is constructed on the slope according to of the choice trend of a recently environmental-friendly countermeasure, there has a limitation about diagnosis and preparation of measure. Also, collapse of tunnel pithead department slope has maximum in construction and countermeasure method of construction choice unlike cut-slope. In this study, analyzed inside circumstance of slope using geophysical exploration for stability analysis and countermeasure inside presentation of tunnel pithead department slope which collapse happens. geophysical exploration used dipole(Dipole-Dipole) method that is based to distribution principle does specific resistance, goes side by side with on-the-spot observation and draws base strength parameter and executed stability analysis, and presented stabilization countermeasure inside of collapse slope on this. I wish to conduce in development and research for use technical development of geophysical exploration technique hereafter by executing geophysical exploration in road collapse spot applying through this study.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.3 s.39
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• pp.39-56
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• 1990

The purpose of this study is to analyze the roadside slope of mountainous Parkway. 48 sites were selected by Random Ranking Sampling. This study was researched on the slope condition with the cause of occurrence, the situation of fundamental engineering works and vegetation on slopes. The main results of this research are summarized as follow ; 1. Slope shapes are shown nine types in cut slope and four types in fill slope. 2. Generally, fill slopes are larger than cut slopes in slop area. 3. Grade is more steep than standard grade. 4. Main engineering works, which constructed for slope stability, are terracing, side-ditch wall, channel, concrete trellis works and wire fence. 5. Roundabout channel were many constructed within the sector of Ukmojeong-Deokdong, but were few constructed within the sector of Banseon-Seongsam pass and Cheoneun Temple-Seongsam pass. 6. Most. of side-ditch wall were constructed of concrete and wet-masonry. 7. In vegetation works, many exterior species were selected. 8. Planting pattern was not combinated with the national park landscape.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.457-464
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• 2000

Stereographic method is a general and basic method to analyse sliding failure potential of rock slope. Region of failure analysis using stereographic method extend to curved slope from straight slope in this paper, Curved slope is defined as the multi-face slope with free surface more than two face and has different characteristics from straight single face slope. Individual daylight envelopes of free surfaces are combined into total daylight envelope of multi-face slope. So, sliding envelope of multi-face slope is the daylight envelope except friction cone. Specially, If only single joint set is developed in the slope, single plane sliding(or plane failure) is impossible in the single-face straight slope, but possible in the multi-face slope. In the multi-face slope with only one joint set, single plane sliding occurs when orientation of sliding plane is between two side slope orientation in the sliding envelope.

• Journal of The Korean Society of Integrative Medicine
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• v.5 no.4
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• pp.1-9
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• 2017

Purpose : This study was conducted among 195 adults in their 20s. To analyze the impact of the slope types of the scapulae on the plantar surface of the foot, the average pressure (AP), the maximum pressure (MP), the average of local distribution values, and the average movement of the center of pressure (COP) of the different slope types of the scapulae were compared. Method : The anterior-posterior slopes of the scapulae were measured by comparing the slopes of the left and right sides of the scapulae based on the differences in the height and the slope of the coracoid process and the angulus inferior scapulae. Those whose left side of the scapulae had an anterior slope were categorized as type 1, and those whose right side of the scapulae had an anterior slope, as type 2. The average plantar pressure, the center of plantar pressure, the maximum plantar pressure, and local distribution values were analyzed using a plantar pressure analyzer of the FSA. Result : In terms of the AP of the left and right feet, there was no statistically significant difference both in types 1 and 2 on the left and right feet. The comparison results of the MP and the average of local distribution values of the two slope types of the scapulae showed that there was no statistically significant difference on the X-axis both in types 1 and 2 on the left and right feet, but that there was a large statistically significant difference on the Y-axis both in types 1 and 2. That is, the MP of the right foot of the left anterior slope type was located more on the hindfoot than that of the right anterior slope type, and the MP of the left foot of the left anterior slope type was located more on the hindfoot than that of right anterior slope type. Conclusion : This study can be used as fundamental data to predict differences in the location and size of the COP and changes in plantar pressure distribution depending on the slope types of the scapulae, and control the distribution for therapeutic purposes.

• Geomechanics and Engineering
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• v.24 no.4
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• pp.389-397
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• 2021

Pile foundation is a typical form of bridge foundation and viaduct, and large-diameter rock-socketed piles are typically adopted in bridges with long span or high piers. To investigate the effect of a mountain slope with a deep overburden layer on the bearing characteristics of large-diameter rock-socketed piles, four centrifuge model tests of single piles on different slopes (0°, 15°, 30° and 45°) were carried out to investigate the effect of slope on the bearing characteristics of piles. In addition, three pile group tests with different slope (0°, 30° and 45°) were also performed to explore the effect of slope on the bearing characteristics of the pile group. The results of the single pile tests indicate that the slope with a deep overburden layer not only accelerates the drag force of the pile with the increasing slope, but also causes the bending moment to move down owing to the increase in the unsymmetrical pressure around the pile. As the slope increases from 0° to 45°, the drag force of the pile is significantly enlarged and the axial force of the pile reduces to beyond 12%. The position of the maximum bending moment of the pile shifts downward, while the magnitude becomes larger. Meanwhile, the slope results in the reduction in the shaft resistance of the pile, and the maximum value at the front side of the pile is 3.98% less than at its rear side at a 45° slope. The load-sharing ratio of the tip resistance of the pile is increased from 5.49% to 12.02%. The results of the pile group tests show that the increase in the slope enhances the uneven distribution of the pile top reaction and yields a larger bending moment and different settlements on the pile cap, which might cause safety issues to bridge structures.