• Journal of muscle and joint health
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• v.17 no.2
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• pp.203-211
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• 2010

Purpose: We aimed to test the validity of the EQ-5D (Euro-Quality of Life-5 Dimension), a brief and simple instrument, in measuring health related quality of life in the patients with osteoarthritis. Methods: 183 participants attending the education programs for osteoarthritis patients at the Health Centers located in Seoul and Gyunggi province area during the periods of June to December in 2009 were interviewed with the EQ-5D and KWOMAC (Korean version of Western Ontario and McMaster Scale). The data were analysed with Spearman correlation coefficents and t-test by using of SPSS/WIN 12.0 version. Results: There was a negative correlation between knee pain, stiffness and difficulty in usual activity of sub category items of KWOMAC and EQ-5Dindex, while there was no correlation between these categories and EQ-VAS. Moreover, as a result of comparing the score of physical function measured by KWOMAC according to the severity degree of the EQ-5Dindex, the group of advanced stage having moderate and severe symptoms reported significantly higher scores of physical function than those of groups having no health problems. Conclusion: The EQ-5D is an acceptable and valid instrument for measuring health-related quality of life in patients with osteoarthritis.

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.286-292
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• 2010

Purpose: Stability of joints and maintenance of range of motion are needed for optimum function. The most common complaint about the elbow joint is joint stiffness. Recent articles have reported good outcomes in the treatment of stiff elbow joints. However, deciding which procedure to use is always difficult. Materials and Methods: Morrey et al. reported that the functional range of motion of the elbow joint is $30-130^{\circ}$ of flexion-extension and $50^{\circ}C$ of supination and pronation. About 90% of daily activities are done using this range of motion. Stiff elbow joints can be classified according to the traumatic events that caused the problem or the location of the main pathology. Intraarticular pathology includes severe articular mismatch, intraarticular adhesions, loss of articular cartilage, mechanical blockade by osteophytes, loose bodies, and hypertrophied synovium. Extraarticular pathology includes severe capsular adhesion due to the trauma or to dislocation, contracture of the collateral ligaments or muscles, bony bridge. Results and Conclusions: The main pathology underlying the loss of extension is the fibrous contracture of the anterior capsule. In this pathology, an anterior capsulectomy would be helpful. The main pathology underlying the loss of flexion is the contracture of the posterior band of medial collateral ligament.

• Journal of the Korean Wood Science and Technology
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• v.42 no.3
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• pp.282-289
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• 2014

After being laminated with a combination of glass fiber reinforced plastic and plywood, the GFRP laminated plate was densificated for 1 hour at $150^{\circ}C$ with pressure of $1.96N/mm^2$. A partial reinforced beam was produced by attaching the 5 GFRP laminated plates to the joint of glulam and the column. In addition, the column to beam joint was produced by using reinforced laminated wooden pin which was made of GFRP sheet and plywood, fiber glass reinforced cylindrical-LVL column. The joint was made of round log, glulam and drift pin as the reference specimen, and its moment resistance was evaluated. As a result, the strength performance of specimens with partial reinforced beams were 1.8 times stronger than the reference specimen on average. Furthermore, rupture was neither occurred on partial reinforced beam nor column. Toughness and stiffness of joints were also fine. The GFRP sheet reinforced laminated plate showed better reinforcement effect than GFRP textile reinforced one. GFRP sheet was inserted into each layer of laminate, and it showed good condition in rotation-angle and strength, therefore it is the most appropriate to reinforce the part of the beam.

• Journal of the Korean Wood Science and Technology
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• v.29 no.4
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• pp.1-8
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• 2001

This study was carried out to investigate the strength and stiffness of drift pinned and bolted joints with steel-plates by the tension-type lateral strength tests. Specimens were solid wood of Pinus densiflora. Bolt and drift pin were jointed with inserted steel plates. Tests were conducted with combinations of two loading directions (parallel to the grain : 0 degree, perpendicular to the grain : 90 degree) and three diameters of fasteners (d = 6 mm, 10 mm, 12 mm). The results obtained were as follow: 1. In the test of the parallel to the grain, maximum loads were increased with increasing of the diameter of bolt and drift pin in the same end distance. In the test of perpendicular to the grain with diameter 10 mm and 12 mm, specimens mostly were failed with horizontal splits in woods reaching the yield load of drift pinned and bolted joints. 2. The ratio of maximum load to the yield load determined by the so-called "5% offset method", was great in bolted joints in the parallel to the grain This trend become more remarkable as the slenderness ratio was increased. 3. The calculated yield strength was agreed well with the experimental results of drift pinned joint(0 degree).

• Journal of Korean Society of Steel Construction
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• v.16 no.6 s.73
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• pp.769-780
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• 2004

This paper's objective is to evaluate the experimental behavior of gap N-joints made of cold-formed, square, hollow steel sections, with a connection plate as a tension member. The principal parameters for testing included the ratio of chord width to thickness, the ratio of brace width to chord width, eccentric ratio, the shape of the compression member, the branch angle, and the stiffening plate of the chord flange. The strength and failure mode were examined through the test for the gap N-joint, consisting of several parameters. Based on the results of the test, the gap N-joints were determined according to the capacity preceding the displacement of the tension, regardless of the width ratio, and the split failure mode-connected surface for a chord in joints. The strength of the gap N-joints increased proportionally as the $2\gamma$(B/T) ratio decreased, and as the width ratio(${\beta}$) of branch to chord increased. Particularly, $2\gamma$(B/T) decreased as the capacity of gap N-joint increased. The results of the test were summarized for the capacity, initial stiffness, ductility, and change of the failure mode of each gap N-joint.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.10
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• pp.773-782
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• 2020

The development of joint FE models for deep learning neural network (DLNN)-based hybrid FEA is presented. Material models of bolts and bearings in the front axle of tractor, showing complex behavior induced by various tightening conditions, were replaced with DLNN models. Bolts are modeled as one-dimensional Timoshenko beam elements with six degrees of freedom, and bearings as three-dimensional solid elements. Stress-strain data were extracted from all elements after finite element analysis subjected to various load conditions, and DLNN for bolts and bearing were trained with Tensorflow. The DLNN-based joint models were implemented in the ABAQUS user subroutines where stresses from the next increment are updated and the algorithmic tangent stiffness matrix is calculated. Generalization of the trained DLNN in the FE model was verified by subjecting it to a new loading condition. Finally, the DLNN-based FEA for the front axle of the tractor was conducted and the feasibility was verified by comparing with results of a static structural experiment of the actual tractor.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.301-304
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• 2008

The stair joints constructed with prefabricated system are general method doing structure design at hinge. If you regarded joints to come in contact with a flight of stairs and a slope of stairs as hinge, the moment performance of joints is not in the least moment, so as the bending moment of the stair case is increased, the reinforcement increase. Also the use is decreased because increasing the joint damage of the vibration & fatigue load. No less the reason constructed with pin the stair joints because the construction efficiency of field work is useable. Recently, they are considering the construction efficiency, while the semi-rigid detail for bending performance of joints is proposed, but for now they don't reflect the detail. Therefore, we proposed that reflecting the method at design semi-rigid joints. We compared the moment performance with the stair joints designed at the rigid joints, semi-rigid joints and pin joints. The nonlinear behavior of staircase core statically indeterminate structure. The result of research is that a bending stiffness modulus bring to reflect the semi-rigid performance, the performance of the semi-rigid joint is better than pin joints, and that is judged the system better seismic and vibration performance because have excellent ductility more than rigid joint.

• Journal of Yeungnam Medical Science
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• v.10 no.1
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• pp.197-211
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• 1993

Recently, the Supracondyle fracture of the femur is so severe and comminuted that it is difficult to treat open reduction and rigid fixation sufficiently due to violent traffic accident and external forces. The associated injuries are accompanied variously. So complications of the supracondyle fractures including joint stiffness, delayed union, infection are serious. However development of internal implant and operation skill result in relatively satisfactory function than conservative management. The authors reviewed 20 cases of the supracondyle fracture of the femur treated at Yeungnam University Hospital from 1989, Dec. To 1992, Jan. The results were as follows : 1. The male was common(70%). The 2nd-4th decade was most(87%). 2. The most common cause of injuries was traffic accident. The rate of open fracture was 35%, most of it was traffic accident. 3. According to the ASIF group classification. 4 cases were type A, 4 in type B, 12 in type C (10 in type $C_2$&$C_3$). 4. Accompanied injuries included multiple fractures in 9 cases and femoral artery injury in 1 case. 5. Among the 20 cases, conservative treatment was done in 5 cases and operative treatment was done in 15 cases. 6. Functional results (by Schatzker criteria) were as follows. The satisfactory results were achieved in 40% of cases in conservative treatment and 67% in operative treatment. 7. The average time of partial weight bearing was 15 weeks. 8. Complications were knee stiffness in 6 cases and 4 in delayed union.

• Journal of Biomedical Engineering Research
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• v.31 no.3
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• pp.199-209
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• 2010

The locking compression plates-distal femur(LCP-DF) are being widely used for surgical management of the extra-articular complex fractures of the distal femur. They feature locking mechanism between the screws and the screw holes of the plate to provide stronger fixation force with less number of screws than conventional compression bone plate. However, their biomechanical efficacies are not fully understood, especially regarding the number of the screws inserted and their optimal configurations. In this study, we investigated effects of various screw configurations in the shaft and the condylar regions of the femur in relation to structural stability of LCP-DF system. For this purpose, a baseline 3-D finite element (FE) model of the femur was constructed from CT-scan images of a normal healthy male and was validated. The extra-articular complex fracture of the distal femur was made with a 4-cm defect. Surgical reduction with LCP-DF and bone screws were added laterally. To simulate various cases of post-op screw configurations, screws were inserted in the shaft (3~5 screws) and the condylar (4~6 screws) regions. Particular attention was paid at the shaft region where screws were inserted either in clustered or evenly-spaced fashion. Tied-contact conditions were assigned at the bone screws-plate whereas general contact condition was assumed at the interfaces between LCP-DF and bone screws. Axial compressive load of 1,610N(2.3 BW) was applied on the femoral head to reflect joint reaction force. An average of 5% increase in stiffness was found with increase in screw numbers (from 4 to 6) in the condylar region, as compared to negligible increase (less than 1%) at the shaft regardless of the number of screws inserted or its distribution, whether clustered or evenly-spaced. At the condylar region, screw insertion at the holes near the fracture interface and posterior locations contributed greater increase in stiffness (9~13%) than any other locations. Our results suggested that the screw insertion at the condylar region can be more effective than at the shaft during surgical treatment of fracture of the distal femur with LCP-DF. In addition, screw insertion at the holes close to the fracture interface should be accompanied to ensure better fracture healing.

• Journal of Oral Medicine and Pain
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• v.38 no.2
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• pp.175-185
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• 2013

Objective : Condyle hypoplasia in temporomandibular joint(TMJ) is often observed in several radiographic views. Mandibular Condyle hypoplasia is frequently confused with osteoarthritis with bony changes in TMJ. This paper investigated clinical characteristics of mandibular condyle hypoplasia as compared with TMJ osteoarthritis. Material and method : 276 patients with TMD were taken clinical and radiological examination and were divided into study group, 189 patients diagnosed with mandibular condyle hypoplasia, and control group, 87 patients diagnosed with TMJ osteoarthritis. And clinical features(Onset, Overjet, Overbite, Noise, Locking, NAS of noise, LOM, pain, MCO, and site of diagnosis and pain)of the two groups were compared. Results : 1. Mandibular condyle hypoplasia and TMJ osteoarthritis were similar in many of the clinical features. 2. Mandibular condyle hypoplasia concordance rates of the radiographic diagnosis site and the pain site was significantly lower than TMJ osteoarthritis. 3. Bilateral mandibular condyle hypoplasia group had more occlusal discomfort, and clenching habits than unilateral mandibular condyle hypoplasia group. 4. Unilateral mandibular condyle hypoplasia group had more unilateral chewing habits and LOM than unilateral TMJ osteoarthritis group. Unilateral TMJ osteoarthritis group had more morning stiffness and higher concordance rates of the radiographic diagnosis site and the click sound site than unilateral mandibular condyle hypoplasia group. 5. Bilateral mandibular condyle hypoplasia group had more usual headaches and overjet than bilateral TMJ osteoarthritis group. Conclusion : Mandibular condyle hypoplasia has somewhat distinguishing clinical characteristics as compared with TMJ osteoarthritis.