• Steel and Composite Structures
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• v.19 no.3
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• pp.547-567
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• 2015

The paper makes the experimental and finite-element-analysis investigation on the seismic behavior of the rebar-penetrated joint between gangue concrete filled steel tubular column and reinforced gangue concrete beam under low cyclic reversed loading. Two specimens are designed and conducted for the experiment to study the seismic behavior of the rebar-penetrated joint under cyclic loading. Then, finite element analysis models of the rebar-penetrated joint are developed using ABAQUS 6.10 to serve as the complement of the experiment and further analyze the seismic behavior of the rebar-penetrated joint. Finite element analysis models are also verified by the experimental results. Finally, the hysteretic performance, the bearing capacity, the strength degradation, the rigidity degradation, the ductility and the energy dissipation of the rebar-penetrated joint are evaluated in detail to investigate the seismic behavior of the rebar-penetrated joint through experimental results and finite element analysis results. The research demonstrates that the rebar-penetrated joint between gangue concrete filled steel tubular column and reinforced gangue concrete beam, with full and spindle-shaped load-displacement hysteretic curves, shows generally the high ductility and the outstanding energy-dissipation capacity. As a result, the rebar-penetrated joint exhibits the excellent seismic performance and meets the earthquake-resistant requirements of the codes in China. The research provides some references and suggestions for the application of the rebar-penetrated joint in the projects.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.4
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• pp.393-404
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• 2003

Statement of problem. Higher incidence of prosthetic complications such as screw loosening, screw fracture has been reported for posterior single tooth implant. So, there is ongoing research regarding stability of implant-abutment interface. One of those research is increasing the implant diameter and prosthetic table width to improve joint stability. In another part of this research, internal conical type implant-abutment interface was developed and reported joint strength is higher than traditional external hex interface. Purpose. The purpose of this study is to compare stress distribution in single molar implant between external hex butt joint implant and internal conical joint implant when increasing the implant diameter and prosthetic table width : 4mm diameter, 5mm diameter, 5mm diameter/6mm prosthetic table width. Material and method. Non-linear finite element models were created and the 3-dimensional finite element analysis was performed to see the distribution of stress when 300N static loading was applied to model at $0^{\circ},\;15^{\circ},\;30^{\circ}$ off-axis angle. Results. The following results were obtained : 1. Internal conical joint showed lower tensile stress value than that of external hex butt joint. 2. When off-axis loading was applied, internal conical joint showed more effective stress distribution than external hex butt joint. 3. External hex butt joint showed lower tensile stress value when the implant diameter was increased. 4. Internal conical joint showed lower tensile stress value than external hex butt joint when the implant diameter was increased. 5. Both of these joint mechanism showed lower tensile stress value when the prosthetic table width was increased. Conclusion. Internal conical joint showed more effective stress distribution than external hex joint. Increasing implant diameter showed more effective stress distribution than increasing prosthetic table width.

• Journal of Acupuncture Research
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• v.32 no.4
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• pp.77-89
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• 2015

Objectives : To evaluate the safety of multiple-dose intramuscular Shinbaro Pharmacopuncture in male and female Sprague-Dawley(SD) rats over a period of 4 weeks(12 sessions). Methods : In order to test the safety of multiple-dose intramuscular Shinbaro Pharmacopuncture we used 40 healthy male and female 6-week old SD rats(male weight 171.79~196.37 g, female weight 127.93~146.43 g). Shinbaro Pharmacopuncture was administered intramuscularly to male and female SD rats at doses of 4.6 (low dose group, n=10), 9.2 (moderate dose group, n=10), and 18.5 mg/kg(high dose group, n=10), respectively. General symptoms, body weight changes, blood tests, biochemical testing, necropsy, organ weight and histopathogical findings were examined over a 4-week period. Results : 1. No mortalities or adverse effects were caused by the investigational substance were observed during the study period. 2. There was no significant difference in body weight caused by the the investigational substance across all groups. 3. No significant between-group difference was found to be caused by the investigational substance in blood tests and biochemical testing. 4. No abnormalities were detected by a necropsy examination with the unaided eye at the macro level after treatment with the investigational substance. 5. Difference in organ weight between groups caused by the investigational substance was not found. 6. All groups did not exhibit pathological findings caused by the investigational substance in histopathogical examination. Conclusions : According to these results, Shinbaro Pharmacopuncture has no systemic or organ toxicity with multiple-dose intramuscular administrations in male and female SD rats over a 4-week period (12 sessions). These results imply that no adverse effects are observed at a level (NOAEL) of Shinbaro Pharmacopuncture of 18.5 mg/kg.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.11
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• pp.1316-1322
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• 2011

Most of the mechanical structures use bolting or spot welding for the whole structure. In recent years, bolting & rivets are used rather than the welding due to reassembly and repair. Analysis of bolted joints is so complicate that many conditions must be considered such as pre-load and contact, etc.. Bolted joint analysis is done by theoretical, experimental & numerical methods. However, numerical analysis in the bolted joint is used because the contact and stress in the joints are changed due to the pre-load. In this study, we analysis the slip and the deformation of the contact area in the joint depending on the pre-load and find the optimized bolting condition.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.22 no.1
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• pp.71-76
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• 2016

Background: The objective of this research is to provide base line data on Korea Baseball rehabilitation treatment by presenting the distribution of upper extremity surgeries according the surgical sites of Korean professional baseball players. Methods: The targets of this research are 561 players from nine Korean baseball clubs. The number of players that have undergone surgery was investigated. In other words, the frequency of shoulder joint surgeries, elbow joint surgeries, and wrist and hand surgeries per each baseball club was investigated. Results: The number of the players who have had surgeries was 151, but among the players, there were some who have had repeated surgeries for which the total number of surgery experience was 162. The result showed that elbow joint surgeries were the most frequently enacted, followed by shoulder joint surgeries, and wrist and hand surgeries. From the nine clubs, Samsung was the club with the highest frequency of surgeries. Conclusions: This research shows that Korean professional baseball players need special training centers with systematic rehabilitation programs. Another conclusion suggests that urgent need for rehabilitation program of upper arm which particularly focused on elbow joint is existing. On the basis of this research, we expect more studies on the specific rehabilitation programs which is categorized by injury areas.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.3
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• pp.265-274
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• 2011

This paper presents current state of the prediction simulator of structural characteristics of machinery equipment accuracy. Developed accuracy prediction simulator proceeds and estimates the structural analysis between the designer and simulator through the internet for convenience of designer. 3D CAD model which is input to the accuracy prediction simulator would simplified by the process of removing the small hole, fillet and chamfer. And the structural surface joints would be presented as the spring elements and damping elements for the structural analysis. The structural analysis of machinery equipment joints, containing rotary motion unit, linear motion unit, mounting device and bolted joint, are presented using Finite Element Method and their experiment. Finally, a general method is presented to tune the static stiffness at a rotation joint considering the whole machinery equipment system by interactive use of Finite Element Method and static load experiment.

• Journal of Oral Medicine and Pain
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• v.46 no.3
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• pp.69-74
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• 2021

As for temporomandibular joint arthritis (TMJ OA), managing the contributing factors at an early stage through accurate diagnosis is necessary to prevent irreversible bone changes. TMJ OA, which is a multi-organ disease caused by various pathophysiological mechanisms, is developed mainly due to mechanical overload. It is a disease characterized by degeneration of articular cartilage and subchondral bone as a low-level inflammatory arthritis condition developed by dysregulation of catabolic and anabolic activity of chondrocytes. Age, mechanical overload sensing of cartilage, chondrocyte apoptosis, catabolic enzymes, inflammatory factors, abnormal remodeling of subchondral bone, and estrogens may be involved in the pathogenesis of arthritis. Therefore, a comprehensive evaluation is needed to diagnose and manage progressive cartilage degeneration, subchondral bone remodeling, and associated symptoms of TMJ OA.

• Journal of Oral Medicine and Pain
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• v.47 no.1
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• pp.67-71
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• 2022

Subchondral cysts are frequently encountered in patients with temporomandibular joint osteoarthritis (TMJ OA), particularly in advanced stage. Subchondral cysts within osteoarthritis are typically lying adjacent to the joint surface where initial load bearing occurs during activity and have been associated with greater pain and disease progression. Although the etiology of these cysts remains uncertain, recently studies report that the induction of the subchondral bone mechanical stress caused subchondral cysts. Repeated overloading leads to further deterioration of subchondral bone which render subchondral bone structure more fragile, increase the risk of osteoarthritis progress. The purpose of this study was to assess the effect of conservative treatment and longitudinal osseous changes of a large subchondral cyst in a mandibular condyle in a symptomatic TMJ OA patient.

• The Journal of Internal Korean Medicine
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• v.36 no.2
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• pp.189-199
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• 2015

Objectives: The marker substances of cultivated wild ginseng pharmacopuncture that may not be detected during the process of steaming remain controversial. We developed a combined cultivated wild ginseng pharmacopuncture that contains all the marker substances. The aim of this experiment was to investigate the marker substances and test the toxicity of the combined cultivated wild ginseng pharmacopuncture. Methods: The marker substances were detected using HPLC. Intravenous injection toxicity studies were conducted at Medvill, an authorized institution for non-clinical studies, under the regulations of Good Laboratory Practice. We observed survival rates, abnormal behaviors, weight changes, gross findings in autopsy, blood biochemical properties, and histological abnormalities of organs such as the liver and kidney. Results: HPLC data showed that ginsenosides Rg1, Rb1, and Rg3 were detected at concentrations of 19.29, 47.64, and 3.02 μ g /ml, respectively. Administration of combined cultivated wild ginseng pharmacopuncture resulted in no dead animals or significant toxicological changes. Conclusions: The combined cultivated wild ginseng pharmacopuncture contains all the marker substances and is a relatively safe treatment medium. Further studies should be conducted to confirm the present findings.

• Research in Community and Public Health Nursing
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• v.28 no.1
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• pp.55-68
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• 2017

Purpose: The purpose of this study is to develop and evaluate a joint health self-management program for knee osteoarthritis elders in communities. Methods: This program was developed based on the IMB (information-motivationbehavioral skills) model. The program methods include education, setting and achieving goals, sharing experiences, telephone counseling, and self-monitoring. The topics of the program include joint assessment, exercise, massage, joint protection, medication, depression management, diet, and healthcare approach. The research was conducted following the principles of the nonequivalent control group pretest-posttest design. Participants were 26 subjects in the experimental group, and 27 subjects in the control group. The experimental group participated in the self-management program, and the control group received general education. Results: Both post-test scores of personal motivation, social motivation, behavior skill, self-management behavior, joint pain, joint stiffness, physical function disability, right knee extension, left knee extension, and depression were significantly different between the experimental group and the control group. Conclusion: The results of the study can be used to develop and standardize a systematic joint health self-management program. Further research is highly recommended to develop a strategy to continuously facilitate self-management of osteoarthritis patients' procedures.