• Physical Therapy Korea
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• v.2 no.2
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• pp.46-55
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• 1995

The purpose of this study was to assess the concurrent validity and reliability of goniometric measurement of joint motion. Subjects were 40 healthy university students. Measurements were performed by 4 inexperienced physical therapy students. Four different instruments were used and three readings were taken with each instrument in random order making a total of 12 readings for flexion of the right elbow of each subject. Goniometers used were 1. universal 2. fluid-based goniometer/inclinometer 3. digital LCD goniometer 4. electronic goniometer/torsiometer. The results were as follows: Concurrent validity was highest (r= .94) with the universal and digital LCD tools. Interrater reliability (Pearson Product Moment Correlation) was good for each tool. Interrater reliability calculated by ICC(2,1) was highest (.96) with the tensiometer and lowest (.78) with the digital LCD goniometer. Intrarater reliability calculated by ICC was excellent (${\geq}.90$) for all instruments. These results show that concurrent validity, intrarater and interrater reliability are very good in the used of all four types of goniometers/inclinometer/tensiometer, even with inexperienced raters. These results confirm the almost universal reliance on hand held goniometers for joint measurement by physical therapists as being a reliable practice. Further research should be done clinically with actual patients.

• Journal of the korean Society of Automotive Engineers
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• v.3 no.3
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• pp.1-7
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• 1981

재래적 자동차의 구동계통은 동력원 즉 engine이 앞에 위치하고 뒤에서 미는 순서로 되어 있다. 그러므로 engine 과 차축을 연결하는 이 축(또는 구동계통)은 engine으로 부터의 힘을 차축으로 전달하는 역할을 하며 기본적으로 비틀상태의 반성부재로서 비교적 큰 회전 insertia를 받게 된다. 구동축은 한 개 또는 그 이상의 universal joint와 solid 상태 또는 관으로 된 축으로 조립 되어 있다. 그리하여 축방향의 동작을 통해서 토오크를 전달하고 일정한 각도 또는 변화되는 각도에서 회전운동을 한다. 차축은 차체 spring을 통해서 부쳐져 있으므로 주행중 구동축은 축 방향의 길이의 변화가 있게 되며 따라서 연결돤 각동작이 일어나며 이를 위해서는 universal joint가 필요하게 되며 따라서 전륜구동차에서도 필요하다. 자동차에 적용되고 있는 구동적에는 두가지 기본형이 있는데 torque tube형 구동방법과 hotchkiss형(또는 open driveline형) 구동방 법이다. Torque tube형 구동방식은 근래에는 사라져 가고 있는데 그 주요원인은 구동계통에서 발생되는 소음이 튜브를 통해 증축 전달되며 수리비용이 비교적 큰 때문이다. 이에 비해 open driveline형의 이점은 제조원가가 낮고, 용이하게 제조할 수 있으며, 종량이 경강되며 장착하기 에도 용이한 점들이다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.211-214
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• 2000

An error analysis is very important for a precision machine tool to estimate its performance. This study proposes a new parallel device, a cubic parallel manipulator. Errors of the proposed cubic parallel manipulator include universal joint errors, errors occurring due to changes in the fore directions in the links, and actuation errors. An error analysis is performed for the manipulator platform moving at uniform velocity. The analysis shows how the position and orientation of the platform influences the directional link forces that change the errors in the manipulator. The analysis shows that the method can be used in predicting the accuracy of parallel devices.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.12
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• pp.109-119
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• 1995

A driveline incorporating universal joints when driving through an angle can excite various components in a vehicle with second order excitation of torsional and bending vibrations, being transmitted either audibly(noise), or physically(vibration). For a certain range of vehicle dpeed noises can be radiated from the cab wall, in which resonances occur by the excitations transmitted from the driveline as a vibration source. In this paper, the excitation mechanism of cab noises is studied especially for the vehicle speed range of 65 .approx. 75 km/h through the simulation for torsional vibrations of the driveline and for bending vibrations of the cab of an 11 Ton grade Cargo Truck, and verified additionally by vibration and noise measurements. As a result, it is found that the uncomfortable noises in the cab are caused mainly by the abrupt increase of the joint angle of driveline near the axle differential resulted from the excessive clearance alignment of the leaf spring gate.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_1
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• pp.993-999
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• 2023

In this paper, a novel polishing tool mechanism with 3-axis compliance is presented, which consists of 2-axis rotational and 1-axis linear compliances in series. The 2-axis rotational compliance mechanism is made up of four cantilever beams for adjusting rotational stiffness and one flexure universal joint at the center for constraining the z-axis deflection. The 2-axis rotational compliance can mechanically adjust the polishing tool to machined surfaces. The polishing press force can be simply controlled by using a linear spring along the z-axis. The 2-axis rotational and 1-axis linear compliance design is decoupled. The stiffness analysis of the 2-axis compliance mechanism was performed based on link compliance matrix and rigid body transformation. A 3-axis polishing tool was designed by configuring the 2-axis compliance mechanism and one linear spring.

• Journal of Technologic Dentistry
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• v.30 no.1
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• pp.49-55
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• 2008

In this study, to provide the fundamental data on stable connection method for successful implants prosthesis, We fabricated the solder joint of gold alloy bar specimens by gas flame soldering method and laser welding and soldering method. It compared and studied the tensile strength of two soldering method by universal testing machine. The results using universal testing machine were as follow : The mean of tensile strength of solder joint bar in gas flame soldering method specimens was 363.89 $\pm$17.62 MPa, and the mean strength of laser welding and soldering method was 125.91 $\pm$ 19.66 MPa, so gas flame soldering method was better than laser welding and soldering method and the finding better way to improve tensile strength is needed in laser welding method. On weak loading condition and the part which is needed an accuracy, laser welding method is more effective and on long-span prosthesis and frequent chewing loading part, laser welding technique is recommended first and applying additional gas flame soldering technique would be better for making much more successful prosthesis.

• ETRI Journal
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• v.38 no.5
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• pp.941-951
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• 2016

In this paper, cognitive radio and simultaneous wireless information and power transfer (SWIPT) are effectively combined to design a spectrum-efficient and energy-efficient transmission paradigm. Specifically, a novel SWIPT-based primary-secondary cooperation model is proposed to increase the transmission rate of energy/spectrum constrained users. In the proposed model, a multi-antenna secondary user conducts simultaneous energy harvesting and information forwarding by means of power splitting (PS), and tries to maximize its own transmission rate under the premise of successfully assisting the data delivery of the primary user. After the problem formulation, joint power splitting and beamforming optimization algorithms for decode-and-forward and amplify-and-forward modes are presented, in which we obtain the optimal PS factor and beamforming vectors using a golden search method and dual methods. Simulation results show that the proposed SWIPTbased primary-secondary cooperation schemes can obtain a much higher level of performance than that of non-SWIPT cooperation and non-cooperation schemes.

• Journal of Veterinary Clinics
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• v.31 no.2
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• pp.121-124
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• 2014

A 7-year-old, intact female Jindo dog was presented for assessment of weight-bearing lameness of the right hindlimb. On physical examination, crepitus and pain was noted in the right coxofemoral joint upon extension. Radiographs revealed a craniodorsal luxation of the right coxofemoral joint and degenerative joint disease (DJD) of both coxofemoral joints. Total hip replacement (THR) was performed for the right coxofemoral joint. Intraoperatively, dorsal acetabular rim (DAR) deficiency was noted, which can be related to a high risk for acetabular cup implant dislocation. Deficiency of the dorsal acetabular rim realigned with the acetabular cup using universal locking plate (ULP) and polymethylmethacrylate (PMMA) bone cement. After surgery, the patient had an uneventful course and a successful outcome. The ROM and thigh girth were dramatically improved. There were no complications associated with prosthesis implants. Hip luxation with dorsal acetabular rim deficiency in a dog was successfully repaired with THR and dorsal acetabular rim augmentation using ULP and PMMA bone cement. This technique should be considered when conventional THR is precluded by dorsal acetabular rim deficiency.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.4
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• pp.75-80
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• 2001

An error analysis is very important to estimate performance of a precision machine. This study proposes an error analysis for a new parallel device, a cubic parallel device. The cubic parallel manipulator has error sources including upper and lower universal joint errors due to the directional changes in the link and actuation errors. The maximum errors of the end effector are affected by the axial direction changes of each links and the clearances of the universal joints when the parallel manipulator is moving along a path. It is found that the changes of errors mostly occur at the positions where the directions of exerting link forces shift. The error analysis is based on an error model formed from the relation between the universal point errors and the end-effector accuracy. The analysis method can be also used in predicting the accuracy of other parallel devices.

• International Journal of Automotive Technology
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• v.8 no.6
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• pp.723-730
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• 2007

The typical design of automotive driveshafts generally utilizes Constant Velocity(CV) joints as a solution to NVH. CV joints are an integral part of vehicles and significantly affect steering, suspension, and vehicle vibration comfort levels. Thus, CV joints have been favored over universal joints due to the constant velocity torque transfer and plunging capability. Although CV joints are common in vehicle applications, current research works on modeling CV joint friction and assumes constant empirical friction coefficient values. However, such models are long known to be inaccurate, especially under dynamic conditions, which is the case for CV joints. In this paper, an instrumented advanced CV joint friction apparatus was developed to measure the internal friction behavior of CV joints using actual tripod-type joint assemblies. The setup is capable of measuring key performance of friction under different realistic operating conditions of oscillatory speeds, torque and joint installation angles. The apparatus incorporates a custom-installed triaxial force sensor inside of the joint to measure the internal CV joint forces(including friction). Using the designed test setup, the intrinsic interfacial parameters of CV joints were investigated in order to understand their contact and friction mechanisms. The results provide a better understanding of CV joint friction characteristics in developing improved automotive driveshafts.