• Tunnel and Underground Space
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• v.17 no.5
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• pp.350-359
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• 2007

Most large cut slopes of open pit mines, roadways, and railways are steeply inclined and composed with rocks that do not contain soils. However, these rock slopes suffer both weathering and fragmentation. In the case of steep slopes, falling rock and collapse of a slope may often occur due to surface erosion. Cast-in place concrete and rubble work are the most widely used earth structure-based pressure supports that act as restraints against the collapse of the rock slope. In order to overcome the shortcomings of conventional retaining walls, a segmental grid retaining wall is being used with connects precasted segments to construct the wall. In this study, laboratory model test was conducted to estimate deformation behavior of segmental grid retaining wall with configuration of rear strecher, height and inclination of the wall. In order to examine the behavior characteristics of a segmental grid retaining wall, this research analyzes the aspects of spacial displacement through relative displacement according to change in the inclination of the wall. Also, the walls behavior according to the formation and status of the rear stretcher which serves the role of transferring the load from the header and the stretcher which make up the wall, the displacement of backfill materials in the wall, and the location of the maximum load were surveyed and the characteristics of displacement in the segmental grid retaining wall were observed. The test results of the segmental grid retaining wall showed that there was a sudden increase in failure load according to the decrease in the wall's height and the size of the in was greatly decreased. Furthermore, it revealed that with identical inclination and height, the structure of the rear stitcher did not greatly affect the starting point or size of maximum horizontal displacement, but rather had a stronger effect on the inclination of the wall.

• Physical Therapy Korea
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• v.29 no.1
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• pp.37-47
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• 2022

Background: Lower back pain (LBP) is a major cause of disability and a common musculoskeletal disorder encountered at some point in life. Dysfunction of the lumbar vertebrae has been associated with decreased flexibility of the hamstrings, which exhibited a strong positive correlation with LBP. Hamstring tension affects lumbar pelvic rhythm. We aimed to activate pelvic stability with compression by Active Therapeutic Movement (ATM), muscle energy technique (MET) was applied to increase the flexibility of the hamstring. Objects: In this study, we aimed to investigate the effects of MET with ATM and general MET were applied to the hamstring of adults, who were in their twenties with nor without LBP, on their pelvic inclination and the length of their hamstring. Methods: A total of 32 subjects were briefed about the purpose of this study and agreed to participate voluntarily. Before the experiment, all subjects were pre-examined, and they were divided into an LBP group and a no lower back pain group accordingly. Thereafter, all subjects participated in both in a crossover manner. After at least one week, they switched to another group and participated in the same experiment. Results: The study results revealed that both groups demonstrated significant results in the modified active knee extension test (p < 0.01) and the sit and reach test (p < 0.01) performed to assess the hamstring flexibility; an interaction (p < 0.05) was noted. Moreover, a more significant difference was observed between the MET with ATM and the general MET. Although significant results were obtained for the pelvic inclination (p < 0.01), interaction was not noted. Conclusion: Conclusively, in this study, when the MET with ATM was applied to the two groups, there was a significant difference compared to the general MET for hamstring flexibility, but it was confirmed that there was no significant difference for the pelvic inclination.

• Journal of Korean Association for Spatial Structures
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• v.16 no.1
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• pp.85-94
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• 2016

In this study, an acceleration sensor that has optical fibers to measure the inclination and acceleration of a structure through contradictory changes in two-component FBG sensors was examined. The proposed method was to ensure precise measurement through the unification of the deformation rate sensor and the angular displacement sensor. A high sensitivity three-axis accelerometer was designed and prepared using this method. To verify the accuracy of the accelerometer, the change in wavelength according to temperature and tension was tested. Then, the change in wavelength of the prepared accelerometer according to the sensor angle, and that of the sensor according to the change in ambient temperature were measured. According to the test results on the FBG-based vibration sensor that was developed using a high-speed vibrator, the range in measurement was 0.7 g or more, wavelength sensitivity, 2150 pm/g or more, and the change in wavelength change, $9.5pm/^{\circ}C$.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.1
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• pp.30-35
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• 2005

An automatic transmission pattern with the fixed standard shift map can provide comfortable shift to driver. However it may be a complain to provide shift by the same shift pattern for driver because the inclination of a driver may be various. Therefore, in this paper, we design the decision module, which can decide the driving style using input to decide the inclination of the driver and driving manner. The goal of this paper is to calibrate the shift map according to the inclination of the driver using the decided driving manner from the proposed module. As a result, the proposed intelligent automatic transmission system can provide a suitable shift point and time to the driver. To verify the performance of the proposed system, the real data that is obtained from the road test will be used.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.4
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• pp.435-445
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• 1997

It was studied the phenomena of transient freezing of an inclined water-saturated enclosure. One side of the test section was cooled and the other sides were insulated. The effects of the initial temperature, the inclination angle on the temperature field and the shape of the ice-water interface were observed. In the beginning of freezing, with increasing the inclination angle the freezing rate was increased and in the stable density layer centered $4^{\circ}C$, the freezing was fast as the convective fluid flow became small. When the initial temperature was above the $4^{\circ}C$, the frozen thickness in the upper part of inclined surface was thinner than that in the lower part, but with time the frozen thickness of upper part was thicker than that of lower part, below the $4^{\circ}C$, the frozen thickness in the upper part was thicker than that of lower part from the begining, and above the $8^{\circ}C$ in the beginning upper part was thinner with concave, but with time thicker the upper part, vanishing concave.

• Computers and Concrete
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• v.33 no.6
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• pp.659-670
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• 2024

The mechanical behaviour of layered concrete samples containing an internal crack was numerically studied by modelling the geo-mechanical specimens in the particle flow code in two dimensions (PFC2D). The numerical modelling software was calibrated with the experimental results of the Brazilian tensile strengths gained from the laboratory disc-type specimens. Then, the samples with the bedding layers and internal notch were numerically simulated with PFC2D under uniaxial compressive loading. In each specimen, the layers' thickness was 10 mm but the layer's inclination angle was changed to 0°, 30°, 60°, 90°, 120° and 150°. Of course, the layers'interfaces are considered to have very low strengths. The internal notch was kept at 3 cm in length however, its inclination angle was changed to 0°, 40°, 60° and 90°. Therefore, a total, of 24 numerical models were made to study the failure mechanism of the layered concrete samples. Considering these results, it has been concluded that the inclination angles of both internal crack and bedding layers affect the failure mechanism and uniaxial compressive strength of the concrete.

• Journal of the Korean Geotechnical Society
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• v.22 no.2
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• pp.5-17
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• 2006

In order to investigate the stabilizing effect of nails against sliding, a series of model tests were carried out. The apparatus of model test was designed to perform the model test of soil slope reinforced by nails. The instrumentation system was used to measure the deflection behavior of nails during slope failure. As a result of model tests, the quantity and the occurred position of the maximum bending stress are changed according to the area ratio and the inclination angles of nails. The maximum stabilizing effect against sliding of nails is presented at 0.7$\%$ of the area ratio because the biggest maximum bending stress occurs at this time. But, the stabilizing effect of nails decreases with more than 0.7$\%$ of the area ratio. In the same condition of the area ratio, the stabilizing effect of nails is excellent at -10$^{circ}$ of the inclination angles of nails. The sliding surface can be predicted on the basis of the position of the maximum bending stress in each nails. The shape and depth of sliding surface are changed according to the area ratio and the inclination angles of nails.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.1
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• pp.40-50
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• 2012

This study aims to analyze the performance of a submersible fish cage which was designed for developing an economical cage system can be applied in korean aquaculture environment easily. To analyze the performance of the designed cage a model test was carried out. In the test, inclination changes of the upper frame and mooring tensions of model cage were measured during the submerging and surfacing motion in still water and wave condition (period: 2s, wave height: 0.1, 0.2, 0.3m). As a result, in the still water condition the model cage kept horizontal balance and inclination degree of the upper frame was about $1^{\circ}$. In the wave condition, the model cage showed bilateral symmetric up-and-down motion but the average inclination degree of the upper frame was about $0^{\circ}$. When the model cage reached at a depth of 1m, the up-and-down motion of the cage was decreased by 12% compared with that of at the surface (period 2s, height 0.3m). In the same wave condition, the maximum and average line tension under the bottom position were about 8% and 11% respectively compared with that of at surface.

• The Journal of Korean Association of Computer Education
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• v.7 no.6
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• pp.117-128
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• 2004

Compared with traditional face-to-face instruction, online learning causes learners to experience more severe feeling of isolation and results in higher dropout rate. This is due to the lack of interaction, sense of belonging, membership, interdependency, cooperation among members and social environment that enables persistence in online learning. Therefore, it is very important for grouping e-learning community to lower the dropout rate and eliminate feeling of isolation. In this paper, the research has been done on the inclination test list to be applied for grouping the desirable learning community. And on the basis of this research, the grouping system for e-learning community(GSE) based on intelligent multi agents for an inclination test using homogeneous and heterogeneous items has been developed. GSE system has such properties that construct a personalized user profile by an agent, and then make groupings according to users' inclination. When this system was evaluated, about 88% of learners were satisfied, and they wanted the group not to be disorganized but to be maintained.

• Tunnel and Underground Space
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• v.16 no.4 s.63
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• pp.313-325
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• 2006

In this study, scaled model tests were performed to investigate the deformation behaviors around tunnels located in anisotropic rocks. Fifteen types of test models which had respectively different joint angles and rock pressure conditions were made, where the modelling materials were the mixture of sand, plaster and water. All of the tested models showed the shear failure mechanism at the stress-concentrated regions and sliding phenomena according to the joint planes. The direction of joint inclination turned out to have great effect on the tunnel deformation behaviors. The models of joint inclination less than $30^{\circ}$ showed considerable floor heavings. The model of $50^{\circ}$ joint inclination showed the least tunnel convergence among the tested models regardless of rock pressure condition, so that it was thought as the most stable model. Furthermore, the failure mechanisms and deformation behaviors of tunnel models were strongly dependent on the coefficient of rock pressure.