• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.4 no.2
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• pp.121-135
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• 2009

Objectives : This study was carried out to investigate the effects of "Yangmuji Anchu Traction Technique" on Temporomandibular Joint Disorder Patient. Methods : The therapies were Chuna("Yangmuji Anchu Traction Technique"), acupuncture treatment, Carthami-Semen Herbal Acupuncture treatment and herbal medicine. We estimated the effects of treatment by measuring from a lower front teeth to upper front teeth in open mouth, measuring a gap of center line on front teeth in open mouth. And by measuring Visual Analog Scale(VAS) and Patient Global Assessment(PGA) before and after treatment. Results : After treatment, we confirmed these improvements : the length measuring from a lower front teeth to upper front teeth in open mouth and the gap of center line on front teeth in open mouth was improved in all cases. Also Visual Analog Scale(VAS) was improved in all cases. Conclusions : These results suggested that "Yangmuji Anchu Traction Technique" effected for Temporomandibular Joint Disorder Patient.

• Journal of Welding and Joining
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• v.16 no.2
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• pp.100-110
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• 1998

In this paper, the laser weldability of thin gage steels for automobile application is discussed. Welding was carried out with a high power carbon dioxide laser system, and the laser energy was concentrated through a plano-convex lens. Test results showed that the joint gap in the butt welding proved to be one of the critical conditions for an acceptable weld. In the case where the ratio of the gap clearance to the material thickness was slightly bigger than optimal value, the weld strength was reduced showing weld metal fracture. It was possible to obtained a weld penetration ratio of 0.91 when the vertical offset ratio was controlled to be 0.4 or smaller. Results also demonstrated that the weld strength of the lap joint was influenced by travel speed. At the travel speeds lower than 37 mm/s, the weld strength indicated higher value than that of class A recommendation strength of a resistance spot weld based on the KS code. It was clear that the complicated effect of specimen alignment should be considered so as to make a sound weld with high integrity when the laser process was applied to the long weld line.

• Structural Engineering and Mechanics
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• v.89 no.1
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• pp.61-75
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• 2024

Strengthening of hollow structural sections using through-bolts is a cost-effective and straightforward approach. It's a versatile method that can be applied during both design and service phases, serving as a non-disruptive and budget-friendly retrofitting solution. Existing research on axially loaded hollow sections T-joints has demonstrated that this technique can amplify the joint strength by 50%, where single bolt could enhance the strength of the joint by 35%. However, there's a gap in understanding their use for K-joints. As the behavior of K-joints is more complex, and they are widely existent in structures, this study aims to bridge that gap by conducting comprehensive parametric study using finite element analysis. Numerical investigation was conducted to evaluate the effect of through bolts on K-joints focusing on using single through bolt to achieve most of the strengthening effect. A full-scale parametric model was developed to investigate the effect of various geometric parameters of the joint. This study concluded the existence of optimal bolt location to achieve the highest strength gain for the joint. Moreover, a rigorous statistical analysis was conducted on the data to propose design equations to predict optimal bolt location and the corresponding strength gain implementing the verified by finite element models.

• 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.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.41
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• pp.18.1-18.10
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• 2019

Background: Temporomandibular joint (TMJ) ankylosis during early childhood may lead to disturbances in growth and facial asymmetry and to serious difficulties in eating as well as in breathing during sleep. The purpose of this study is to describe the effectiveness of an interocclusal splint (IOS) for active mouth opening exercises in the treatment of TMJ ankylosis. Methods: A total of nine patients with 13 instances of TMJ ankylosis from 2008 to 2010 were included in this study, of which five patients were male and four patients were female. Five patients demonstrated unilateral ankylosis, while five patients showed bilateral symptoms. Ankylosed mass resection with coronoidectomy, fibrotic scar release, and resection of stylohyoid ligament calcification was performed with gap arthroplasty without an interpositional graft, and all patients were assessed for maximum mouth opening (MMO) during a mean 6.6-year follow-up period. Results: All patients were subjected to postoperative mouth opening exercises from the day of the operation with the help of an IOS, which was based on an impression taken during surgery. All patients were sufficiently comfortable moving their mandible according to the IOS's guiding plane and impingement, and satisfactory results were achieved, in which MMO was improved by 35 mm more than 6 years after surgery. Conclusions: Complete and adequate resection of the ankylosed mass and postoperative active mouth opening exercises are essential in the treatment of TMJ ankylosis. Moreover, a more comfortable mouth opening guide and interdigitation can be achieved using an IOS, and newly organized fibrosis in the gap space between the newly made resected condylar head and temporal fossa can be suggested.

• The Journal of Advanced Prosthodontics
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• v.2 no.4
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• pp.117-121
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• 2010

PURPOSE. The present study was intended to evaluate the effect of soldering techniques with infrared ray and gas torch under different gap distances (0.3 mm and 0.5 mm) on the tensile strength and surface porosity formation in Ni-Cr base metal alloy. MATERIALS AND METHODS. Thirty five dumbbell shaped Ni-Cr alloy specimens were prepared and assigned to 5 groups according to the soldering method and the gap distance. For the soldering methods, gas torch (G group) and infrared ray (IR group) were compared and each group was subdivided by corresponding gap distance (0.3 mm: G3 and IR3, 0.5 mm: G5, IR5). Specimens of the experimental groups were sectioned in the middle with a diamond disk and embedded in solder blocks according to the predetermined distance. As a control group, 7 specimens were prepared without sectioning or soldering. After the soldering procedure, a tensile strength test was performed using universal testing machine at a crosshead speed 1 mm/min. The proportions of porosity on the fractured surface were calculated on the images acquired through the scanning electronic microscope. RESULTS. Every specimen of G3, G5, IR3 and IR5 was fractured on the solder joint area. However, there was no significant difference between the test groups (P > .05). There was a negative correlation between porosity formation and tensile strength in all the specimens in the test groups (P < .05). CONCLUSION. There was no significant difference in ultimate tensile strength of joints and porosity formations between the gas-oxygen torch soldering and infrared ray soldering technique or between the gap distance of 0.3 mm and 0.5 mm.

• The Journal of Korean Academy of Prosthodontics
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• v.39 no.3
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• pp.297-305
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• 2001

Statement of problem. There have been previous studies about instability according to screw material by means of calculating preload in tightening screw or recording of the torque necessary to loosen screw after tightening screw. Purpose. The purpose of this study was to evaluate screw joint stability through the analysis of fitness at the mating thread surfaces between implant and screw after tightening screws made of different materials. Material and methods. In this study, screws were respectively used to secure a cemented abutment to a hexlock implant fixture; teflon coated titanium alloy screw and titanium alloy screw(Steri-Oss), gold-plated gold-palladium alloy screw and titanium alloy screw(Implant Innovation), gold screw and titanium screw(AVANA Dental Implant System). Each abutment screw was secured to the implant with recommended torque value using a digital torque controller. Each screw was again tightened after 10minutes. All samples were cross sectioned with sandpaper and polished. Then samples were evaluated with an scanning electron microscope analysis. Results. In titanium alloy screw, irregular contact and relatively large gap was present at mating thread surface. Also in teflon-coated titanium screw, incomplete seating and only partially contact was present at the mating thread surface. In gold-plated gold-palladium alloy screw, relatively close and tight contact without the presence of large gap was present by existing of gold coating at the mating thread surfaces. In gold alloy screw, relatively small gap between the mating components was seen. Conclusions. This result suggested that gold plated gold-palladium alloy screw and gold alloy screw achieved a greater degree of contact at the mating thread surfaces compared to titanium alloy screw and teflon-coated titanium alloy screw.

• The Journal of the Korean dental association
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• v.16 no.5 s.108
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• pp.366-371
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• 1978

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1388-1393
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• 2003

In this study, analytic stress-displacement solutions are obtained by using a shear lag modeling constructed for the spliced joint area with a splicing gap filled with adhesive material of elastic modulus $E_{a}$ in the fiber metal laminate (FML) which is known to have excellent fatigue, corrosion and fire-flame resistant characteristics while with relatively low densities compared to the conventional aluminum alloys for lightweight structures.

• Journal of Mechanical Science and Technology
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• v.14 no.11
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• pp.1225-1231
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• 2000

This paper proposes a V-shaped Lyapunov function approach for the model-based control of flexible-joint robots, in which a new model-based nonlinear control scheme is designed based on a V-shaped Lyapunov function. The proposed control guarantees global asymptotic stability for link trajectory control while keeping all internal signals bounded. Since joint flexibility is used as a control parameter, the proposed control is not restricted by the degree of joint flexibility and be applied to flexibility-joint, partly-flexibility, or rigid-joint robots without modification. the effectiveness of the proposed control has been by computer simulation.