• Journal of the Korean Society of Industry Convergence
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• v.4 no.4
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• pp.379-386
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• 2001

The lower toughness or brittle materials for mechanical test lead to the additional requirement that applied displacements be controlled with high resolution. Biaxial tension and shear tester using stepper motor with harmonic driver is shown. The device had to be high resolution so that the crack initiation process of slow extension and steady growth could be examined, Grip plates were connected to a linear bearing and actuator. The actuators consisted of stepper motors with harmonic driver connected to pre-loaded ball screw and nut assemblies. The encoders and motor controllers were connected to a personal computer so that arbitrary displacements histories could he prescribed in normal and tangential directions. The linear bearings were used to react loads perpendicular to their axes while allowing low friction, parallel movement of the attached grips. Load cells measured the reactions normal and tangential. the loads measured the reactions were recorded by the computer.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.63-68
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• 1999

Because misaligned shafts have caused noise, vibration, bearing failures, and stress concentration of coupling part, which decrease the efficiency and life of a shaft system, the proper alignment of shaft system should be monitored continuously in dynamic condition. To solve these problems under dynamic condition, a telemetry system is this study is used to find the condition of the least bending moment, which is known by analyzing the structure and stress induced by misalignment is investigated. The moment derived from two shaft strain at the nearby coupling is measured. The bending strain is measured 5 times for average in static state as well as dynamic state with 100~700 rpm.

• Journal of the Korean Society of Physical Medicine
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• v.5 no.1
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• pp.113-123
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• 2010

Purpose : The purpose of this study was to investigate how upper-extremity-movement of PNF(proprioceptive neuromuscular facilitation) with elastic band has effected on arrangement of body and weight-bearing. Methods : The object has worked with 20 patient

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.4
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• pp.412-418
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• 2020

Generally, the propeller shaft that constitutes the ship shaft system has different patterns of behavior due to the ef ects of engine power, propeller load and eccentric thrust, which increases the risk of bearing failure by causing local load variations. To prevent this, different studies of the propulsion shaft system have been conducted focused the relative inclination angle and oil film retention between the shaft and the support bearing, mainly with respect to the Rules for the Classification of Steel Ships. However, in order to secure the stability of the propulsion shaft via a more detailed evaluation, it is necessary to consider dynamic conditions, including the transient state due to sudden change in the stern wakefield. In this context, a 50,000 DWT vessel was analyzed using the strain gauge method, and the effects of propeller shaft movement were analyzed on the starboard rudder turn which is a typical transient state during normal continuous rate(NCR) operation in ballast draught condition. Analysis results confirm that the changed propeller eccentric thrust acts as a force that temporarily pushes down the shaft to increase the local load of the stern tube bearing and negatively affects the stability of the shaft system.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.129-132
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• 2008

All bearing device should be examined to determine that they are functioning properly. Small changes in other portions of the structure, such as pier or abutment settlement, may be reflected in the bearings. Bearings should be checked to see that they can move freely and are clear of all foreign material. Shoes should be in proper position relative to the temperature at the time of the inspection. Check anchor bolts for any damage and to see that nuts are secure. See that anchor bolt nuts are properly set on the expansion bearings to allow normal movement. In this paper, rehabilitation method for damaged bearings is proposed and damage example of the skewed bridge is illustrated

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.10
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• pp.850-855
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• 2008

This paper suggests a new linear motor which is able to levitate as well as move its mover without any linear bearing or even additive windings. Its structure is very similar to a well-known both-sided linear motor which consists of two stators and a common mover. And the movement principle is the same with that of conventional linear motor. But unlike the conventional one, the amplitudes of phase currents are controlled to levitate the mover. In this paper, the structure and principle of the suggested bearingless linear motor are introduced in detail and its feasibility is experimentally investigated. Using the prototype and a very simple controller, we succeeded in the levitation and linear movement of the mover at a time.

• The Korean Journal of Pain
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• v.8 no.2
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• pp.293-297
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• 1995

Despite applying recent advances in research and technology and taking into acount proper histories and performing thorough physical examinations, a high percentage of patients with low back pain have no identifiable pathology. Problems especially of the sacroiliac joint are commonly missed. The purpose of this article is to describe the effects of sacroiliac injection of local anesthetics and corticosteroids on patients with acute sacroiliac sprain. The sacroiliac joints are essentially nonweight-bearing joints that allows a small amount of anteroposterior rotatory movement around transverse axis usually about 5 to 10 cm below the promontory of the sacrum vertically. The ligamentous portion of sacroiliac joint is vulnerable to rotatory movement particularly when the individual is in an awkward position. Injections of 3 ml of 2% lidocaine and 10 mg of methylprednisolone were given twice at two day intervals to 26 patients with acute sacroiliac sprain. Most of those patients obtained excellent results without any adverse effects.

• PNF and Movement
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• v.14 no.3
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• pp.177-183
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• 2016

Purpose: The purpose of this study was to investigate the effects of neck patterns in proprioceptive neuromuscular facilitation (PNF) for neck movement and the neck disability index (NDI) among adults with forward head posture. Methods: Thirty-nine subjects were randomly assigned into two groups. Subjects in the proprioceptive neuromuscular facilitation exercise group (PNFG, n = 20) received 20 minutes of PNF neck pattern (flexion-Rt. lateral flexion-Rt. rotation followed by extension-Lt. lateral flexion-Lt. rotation) 3 times weekly for 4 weeks. Outcomes were measured using absolute rotation angle (ARA), anterior weight bearing (AWB), range of flexion and extension motions (RFEM), and neck disability index (NDI) methods before and after the 4-week intervention period. Results: There were significant effects for the PNFG, pre- and post-intervention, in ARA, AWB, RFEM, and NDI. There were significant differences in ARA, AWB, RFEM, and NDI compared with CG. Conclusion: The results of this study suggest the PNF neck pattern could be beneficial for adults with forward head posture.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.3
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• pp.38-46
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• 2023

In this study, a bearing test was performed and analytically evaluated to evaluate the bearing performance according to the application of the aluminum stiffener in round-end concrete. In the bearing strength test, the change in bearing performance due to the aluminum stiffener using the aluminum form for manufacturing concrete with round-end, and the steel anchor bolts for member movement and assembly was confirmed. The FE analysis model was identically configured to the experimental conditions, and the result was compared with the experiment. Also, the crack patterns and stress behavior were confirmed. In addition, the effect of strength change of the aluminum stiffener on the round-end concrete was also evaluated analytically. The bearing strength of the round-end concrete increased by about 20% due to the aluminum stiffener, and it was confirmed that the steel anchor bolt did not affect the bearing strength. The maximum load and crack patterns shown as a result of FE analysis were similar to those of the experiment. As a result of FE analysis according to the strength change of the aluminum stiffener, the maximum load change according to the increase and decrease of the strength of the aluminum stiffener by 10% and 20% was evaluated to have no significant effect at a maximum of about 4% compared to before the strength change.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.3C
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• pp.105-111
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• 2012

Bucket foundations, which are used in the foundations of offshore wind turbines, should be able to withstand large amounts of horizontal and moment loads. Tripod bucket foundation, which combines three single buckets, has been used to increase horizontal and moment capacities. This study performed numerical analysis using ABAQUS (2010), to analyze the group effect and the bearing capacity of a tripod bucket in clay. Parametric studies were performed varying the bucket spacing ratio S/D (S=spacing between the centers of the bucket and the tower; D=diameter of the bucket) and depth ratio L/D (L=embedded length of skirt). The applied constitutive models were a linear elastic perfectly plastic model with Tresca yield criteria for normally consolidated clay and an elastic model for buckets. Loading in the vertical, horizontal, and moment directions was simulated with an increase in each movement at a reference point. The bearing behavior and the capacities of a single and a tripod bucket were compared. Capacity evaluation method of the tripod bucket was suggested using the capacity of a single bucket.