• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1302-1306
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• 2007

Joints are used extensively in various industries. For instance, structural adhesives are used in place of the traditional mechanical fasteners, such as screws and bolts, because they are much lighter and spread the stresses more uniformly across the joints. For efficient designs of joints, knowledge of static and dynamic characteristics of joints is essential. Most analysis of joints are carried out using analytical equations or finite element method. In this paper, the characteristics of four conditions of lap-joint beam are investigated experimentally. The mode shapes and nodal points of beam show that there are different deformations in each condition. These deformations may cause high stresses and may initiate local cracking and delamination failures.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.1
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• pp.142-149
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• 1995

This paper presents a new kinematic control strategy for serial redundant manipulators which gives repeatability in the joint space when the end-effector undergoes some general cyclic motions. Theoretical development has been accomplished by deriving a new inverse kinematic equation that is based on springs being conceptually located in the joints of the manipulator. Although some inverse kinematic equations for serial redundant manipulators have been derived by many researchers, the new strategy is the first to include the free angles of torsional springs and the free lengths of the translational springs. This is important because it ensures repeatability in the joint space of a serial redundant manipulator whose end-effector undergoes a cyclic type motion. Numerical verification for repeatability is done in terms of Lie Bracket Condition. Choices for the free angle and torsional stiffness of a joint (or the free length and translational stiffness) are made based upon the mechanical limits of the joints.

• Journal of Veterinary Clinics
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• v.16 no.2
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• pp.497-500
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• 1999

A 4 years old male mixed breed dog, which weighed 25.5 kg, referred to Veterinary Teaching Hospital at College of Veterinary Medicine in Chonnam National University, because of chronic hindleg lameness. Click sound by flexion and extension of stifle joint, positive reaction by cranial drawer movement, fat pad sign and tibial position in cranial drawer position on the lateral radiographic view, medial patellar luxation (grade II), and lameness score 2.5 at standing and 2 at walking in right hindleg were showed. Under general anesthesia with enflurane, after medial arthrotomy, it was performed to remove remnants of cranial cruciate ligament and torn medial menisci and joint closed. In modified retinacular imbrication technique, one lateral fabellar/tuberosity suture, one medial fabellar/tuberosity suture, and one imbrication suture adjacent to the patella were placed. At 9 days after operation, lameness score 0 was observed and general condition was excellent.

• The Journal of the Korean dental association
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• v.19 no.4 s.143
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• pp.375-380
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• 1981

Unilateral bony ankylosis of temporomandibular joint is not extremely rare. Treatment in all cases should be surgical. Considerable difficulty has been encountered by surgeons in the judgment of the planning of the treatment for anklosis; either by gap arthroplasty or by interposition arthroplasty. A recent review of the literautre reveals that many authors reported more of the interposition arthroplasty treatment because of no recurrence and the excellent results obtained. This 22-year-old Korean female, who had suffered from unilateral temporomandibular joint recurrent anklosis, was received an operation of ramus osteotomy followed by interpositional arthroplasty with using of thin gold plate. She formerly was received condylectomy twice at the age of 8 and 9, under the diagnosis of unilateral bony ankylosis due to trauma. My experience with alloplasty in unilaterally recurrent ankylosed T-M joint is presented here for her general and oral functional condition proved to be satisfactory after 4 years follow-up.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.1 no.1
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• pp.29-34
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• 2001

This paper is devoted to investigating direct adaptive neural control of nonlinear systems with uncertain or unknown dynamic models. In the direct adaptive neural networks control area, theoretical issues of the existing backpropagation-based adaptive neural networks control schemes. The major contribution is proposing the variable index control approach, which is of great significance in the control field, and applying it to derive new stable robust adaptive neural network control schemes. This new schemes possess inherent robustness to system model uncertainty, which is not required to satisfy any matching condition. To demonstrate the feasibility of the proposed leaning algorithms and direct adaptive neural networks control schemes, intensive computer simulations were conducted based on the flexible joint robot systems and functions.

• 연구논문집
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• s.27
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• pp.175-181
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• 1997

Superconducting joints between Bi-2223/Ag tapes are fabricated by a press & reaction anneal and a multiple press & anneal. The silver sheath was mechanically or chemically removed from one side of each tape without altering the superconducting core. The exposed superconducting core of the two tapes were brought into contact and pressed so as to form a lap joint. The joined tapes were then subjected to a series of different thermomechanical treatments to achieve optimum heat treatment condition. The result from transport measurements shows that critical current ($I_c$) transmitting through joined area reaches 9A, approximately 60% of the current capacity of the tapes themselves. The critical current through joined area was improved by repeated press and reaction annealing. Measurements of the current-voltage relationship were made with several configuration of the voltage probes to characterize the critical current variation and I-V curve along the joint. Also discussed are microstructural aspects of the superconducting joint.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.5
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• pp.305-309
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• 2012

Temporomandibular joint (TMJ) subluxation and dislocation are uncommon but very unpleasant and distressing conditions to patients. Subluxation of the TMJ is an excessively abnormal condylar excursion secondary to flaccidity and laxity of the capsule. When the condyle head excurses anterior to the eminence upon wide opening, it can return to the fossa by self-manipulation or non-surgical conservative reduction. Surgery is recommended if a complete dislocation, so-called open lock, occurs as a chronic or recurrent protracted condition that cannot be reduced voluntarily. A range of surgical procedures can be performed to limit condylar hypermobility inclusing soft tissue tethering, creation of articular obstacles, removal of mechanical blockade and augmentation of articular eminence using different kinds of grafts. In the present case, a 74-year-old woman was diagnosed with a chronic TMJ dislocation that had lasted for 6 months. Bilateral condylectomy was performed and the post-operative results were good without functional limitations or recurrence.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.6
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• pp.535-538
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• 2011

Malignant otitis externa (MOE) originates as inflammation of the epidermis in the external auditory canal, and spreads to the surrounding structures and neck, leading to abscess formation. MOE is associated with an immunosuppressive condition and diabetes. Patients with MOE suffer from otalgia, otorrhea and hearing loss. According to the literature, surgery to the temporomandibular joint is controversial as the treatment of choice.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.110-113
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• 2002

As a preliminary study for the three dimensional failure analysis of composite joints, the three dimensional stress analysis on a pin-loaded unidirectional-fabric hybrid composite joints are performed. The contact and frictions between composite plate and metal bush are considered in the finite element method by NASTRAN. Experiments are conducted to validate the accuracy and feasibility of the finite element technique for 25 specimens with 5 different geometries. The finite element and experimental results show the bush cap induces the unsymmetric deformation, stress distribution, and failure behavior through the thickness. The experiment also shows the failure loads are higher in the joint with bush cap than without it.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.4
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• pp.137-145
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• 1991

A universal joint is a connecting device of two hinges which can transmit torque from one shaft to another at fixed or at varying angles of intersection. It has been used properly not only as rotational but also as intermittent motion. For the particular kinematics condition of a universal joint, torsional and bending vibrations are produced excessively in an elastic driveline. In this paper only the torsional vibration behavior of a driveline with universal joints is analyzed numerically with the discrete model and a design method of the dynamic vibration damper is proposed, in order to reduce torsional vibrations especially in resonance region as a result of parametric variation.