• Geotechnical Engineering
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• v.12 no.1
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• pp.35-46
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• 1996

An instrumentation system is designed to observe the behavior of slope soil and stabilizing piles during heavy rains. Inclinometers, standpipe piezometers and strain gages are installed into a cut slope reinforced by a row .of piles for an apartment. The horizontal deflection and bending stress developed on the piles can be measured, respectively, by the inclinometers and strain gages installed in piles, while the horizontal deformation of the slope soil can be measured by the inclinometer installed in the soil across the open space between piles. The groundwater level doss not grow so sensitively during heavy rain. The behavior of piles and slope is 서footed by the wetting front, since the driving force of slope increases with the weight of slope soil above the wetting front. The stabilizing piles and the slope soil show elastic behavior during heavy rain.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.7
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• pp.98-104
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• 2004

A spacecraft alignment measurement requires highly precise measurement accuracy which is less than ${\pm}0.5^{\circ}$. In general, such an alignment measurement has been performed by using three or more theodolites. However, it contains the latent accuracy error because of a position stability of spacecraft, etc. The new alignment measurement system which consists of a theodoilte, a rotating table and a digital inclinometer has been developed to possibly to possibly reduce the error. This paper describes the concept and methodology of methodology of measurement system. It was found that new measurement system can provide more accurate results than the conventional system.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.6
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• pp.33-43
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• 2009

This study analyzed data on the pore water pressure, the ground water level, the horizontal displacement and the resistivity monitoring from instrument system, which is established to evaluate the safety in reservoirs. The pore water pressure in the embankment ranged from $0.035{\sim}1.116kg/cm^2$. The seepage that piping showed, as well as the leakage from the reservoirs are acceptable for the safety management of the reservoir. The maximum horizontal displacement and direction analyzed from the measured inclinometer data gives us very effective information to evaluate the safety in reservoirs. The resistivity monitoring technique, which is obtained on the reservoir crest, is an efficient tool to detect leakage zone. The safety index (SI) was predicted by the resistivity monitoring, and was evaluated to have a safety level of 0.8-1.0 at all reservoirs. Safety evaluations of reservoir through instrument systems are effective when studying the embankment, when the results of the instrument system have been analyzed compositively.

• Physical Therapy Korea
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• v.19 no.4
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• pp.8-15
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• 2012

Posterior shoulder muscle tightness is frequently observed in shoulder impingement syndrome because tightness in the posterior portion of the shoulder muscles can cause anterior and superior translation of the humeral head in relation to the glenoid fossa. The purpose of this study was to determine the immediate effects of soft tissue massage on acromiohumeral distance (AHD), anterior translation of the humeral head, and glenohumeral (GH) range of motion (ROM) in subjects with posterior shoulder muscle tightness. Twenty-seven subjects with greater than $10^{\circ}$ difference in the range of GH horizontal adduction between right and left sides were recruited. The range of GH horizontal adduction and internal rotation were measured by a digital inclinometer. The AHD and anterior translation of the humeral head were measured using ultrasonography. A paired t-test was used to compare AHD, anterior translation of the humeral head, and the range of GH horizontal adduction and internal rotation before and after soft tissue massage. The results showed that AHD increased significantly (p<.05) and the anterior translation of humeral head decreased slightly, but not significantly (p=.40) after the soft tissue massage. Furthermore, the ROM of horizontal adduction and internal rotation in the GH joint increased significantly after the soft tissue massage (p<.05). These findings indicate that soft tissue massage on posterior shoulder muscle tightness is an effective method to increase AHD and ROM in the horizontal adduction and internal rotation of the GH joint.

• Geotechnical Engineering
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• v.9 no.1
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• pp.59-68
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• 1993

In deep excavations for creation of underground spaces, it would be difficult to predict earth pressure, especially multilayered ground including rock strata. The earth pressures and displacements on the retention walls are measured by load cell, strain gauge and inclinometer which were installed at struts or anchors at 4 deep excavation sites in Seoul area. In this paper, the measured earth pressure from the struts or anchors are compared with Peck's empirical values, and the coefficient of the earth pressures for each strata and horizontal wall displacement are investigated. The coefficient of earth pressure distribution, a(0.65zka), in the flexible and the rigid walls was about 74% and 88% of Peck's value respecitively. The measured earth pressure distributions for the 4 sites showed about 70%∼80% of Peck's empirical values and the average earth pressure coefficients based on the measured data were 0.3 for the felted layer, 0.23 for the weathered rock and 0.19 for the weak rock. The maximum w리1 displacements were found to be less 0.2% of excavation depth.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.947-954
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• 2008

Nowadays many urban subways are frequently constructed under the building and the river by the use of tunneling method. Especially, the majority of the tunnel are constructed even with shallow depth under the ground in the weathered soil. Since the tunnel are generally designed on the basis of the geographic soil investigation, the stability of the tunnel should be checked with the realistic data instrumented during construction. The displacement of the tunnel occurs in front of the end face during the excavation of the tunnel, which is called as pre-displacement. The total displacement can be figured from the exact pre-displacement, which is very difficult to measure without using any device installed in front of the tunnel end face. In this study, the pre-displacement measured from horizontal inclinometer was analyzed to know the co-relation with the total displacement and also, the trend and the characteristics of the tunnel deformation during construction was suggested through the regression analysis of the measured data.

• Journal of the Korean Geosynthetics Society
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• v.3 no.1
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• pp.3-15
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• 2004

Geogrid reinforced soil structures with segmental block facing have been increased since 1990's, because of the convenience of installation and the flexible appearance. In this paper, the behavior of the segmental reinforced retaining wall was analysed with the results of field monitoring. The height and length of reinforced wall are 12m and 25m, respectively. The field measurement equipments are horizontal and vertical earth pressure cells, settlement plate, strain gauge, inclinometer, and displacement pin. Based on the field monitoring, the horizontal earth pressure was approximately 0.3times higher than that of the theoretical method and the maximum tensile strength of reinforcement was 26.2kN/m. The displacement of facing wall was 23mm at the point of 7.1m height of the wall and toward the wall facing. The results of the study indicate that the segmental reinforced retaining wall is in a stable condition because of good compaction & reinforcement effects, and long period of construction time. Finally, the computer program of SRWall is very useful tool to design the segmental reinforced retaining wall.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.1
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• pp.65-76
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• 2006

In this study, NATM can reduce the loosened ground near the tunnel face more than the other pre-existing tunnelling methods, because of rapid supporting by means of shotcrete and rock bolts. However, this method sometimes can not help for a unstable tunnel face with a unsupported caondition. In order to keep from that dangerous case, some excavation methods such as bench cut and drift advancing method are introduced, despite of high construction cost and period. So, this thesis is intended to introduce the new tunnel face shape, that is concave shaped face, and discusses its effects on the tunnel stabilization.

• Tunnel and Underground Space
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• v.18 no.5
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• pp.338-342
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• 2008

Longitudinal deformation profile(LDP) has been obtained mostly by numerical analysis. In this study, LDP was plotted by measured data from horizontal inclinometer and crown settlement. Deformation of foe ahead was determined by comparing to the maximum deformation point and deformation of after excavation was determined by regression of the measured crown settlement data. The result shows that crown deformation began as f3r as 3D ahead of the face. Crown settlement at the face was 40% of ultimate deformation, which was 10% higher than numerical results, and the deformation converged after excavation of 4D.

• Journal of Astronomy and Space Sciences
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• v.26 no.1
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• pp.47-58
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• 2009

In this study, a Hardware-In-the-Loop (HIL) simulator using thrusters is developed to validate the spacecraft attitude system. To control the attitude of the simulator, eight cold gas thrusters are aligned with roll, pitch and yaw axis. Also linear actuators are applied to the HIL simulator for automatic mass balancing to compensate the center of mass offset from the center of rotation. The HIL simulator consists of an embedded computer (Onboard PC) for simulator system control, a wireless adapter for wireless network, a rate gyro sensor to measure 3-axis attitude of the simulator, an inclinometer to measure horizontal attitude, and a battery set to supply power for the simulator independently. For the performance test of the HIL simulator, a bang-bang controller and Pulse-Width Pulse-Frequency (PWPF) modulator are evaluated successfully. The maneuver of 68 deg. in yaw axis is tested for the comparison of the both controllers. The settling time of the bang -bang controller is faster than that of the PWPF modulator by six seconds in the experiment. The required fuel of the PWPF modulator is used as much as 51% of bang-bang controller in the experiment. Overall, the HIL simulator is appropriately developed to validate the control algorithms using thrusters.