• Journal of Mechanical Science and Technology
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• v.15 no.12
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• pp.1639-1646
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• 2001

It is often necessary that the joints characteristics should be determined in the early stage of the vehicle body design. The researches on identification of joints in a vehicle body have been performed until the recent year. In this study, the joint characteristics of vehicle structure were expressed as the condensed matrix forms from the full joint stiffness matrix. The condensed joint stiffness matrix was applied to typical T-type and Edge-type joints, and the usefulness was confirmed. In addition, it was applied to the real center pillar model and the full vehicle body in order to validate the practical application.

• International Journal of Automotive Technology
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• v.3 no.3
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• pp.117-122
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• 2002

Joint stiffness can affect the vibration characteristics of car body structures. Therefore, it should be included in vehicle system model. In this paper, a numerical approximation of joint stiffness is presented considering joint flexibility of thin walled beam-jointed structures. Using the proposed method, it is possible to optimize joint structures considering the change of section shapes in vehicle structures. The numerical approximation of joint stiffness is derived using the response surface method in terms of beam section properties. The study shows that joint stiffnesses can be effectively determined in designing vehicle structures.

• Journal of Korean society of Dental Hygiene
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• v.17 no.4
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• pp.601-611
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• 2017

Objectives: The purpose of this study is to identify the perceived symptoms of oral and temporomandibular joint disorders in adults and to analyze the factors affecting subjective symptoms of temporomandibular joint disorders. Methods: 249 adults over 20 years old who had subjective symptoms of temporomandibular joint disorders were surveyed and analyzed. Independent t-test and ANOVA test were used to examine the relationship between oral habits and temporomandibular joint disorder according to general characteristics. $Scheff{\acute{e}}$ test was used for post-hoc analysis. Multiple regression analysis was conducted to examine the factors affecting oral habits and temporomandibular joint disorder. Results: First, the factors affecting oral and habitual behaviors were married (p<0.05) and monthly income between 1 million~1.9 million won (p<0.001), higher temporomandibular joint disorder (p<0.01) And the degree of habit was increased. Second, the factors affecting temporomandibular joint disorder were increased in occupation (p<0.05) and the degree of oral habit (p<0.01). Conclusions: In conclusion, it was confirmed that oral habit influences temporomandibular joint disorder. Especially, it is suggested that prevention and promotion of temporomandibular joint disorder are needed to recognize the removal of oral habits.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.10 no.2
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• pp.244-253
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• 2003

Purpose: This study was done for the purpose of testing the effects of hand moxibustion on pain in the knee joint, range of motion of the knee, and discomfort during ADL in elderly persons with knee joint pain. Method: Nonequivalent control group pre-post test research design was used. The participants were 35 elders who had knee joint pain. Sixteen were assigned to the experimental group and 19 to the control group. The instruments used for this study were the CRS (Graphic rating scale) for knee joint pain, goniometer for knee joint ROM, and modified ADL questionnaire developed by Lee. Analysis of data was done by percents, means and standard deviation, $x^2$-test, t-test, and ANCOVA using SPSS WIN 10.0. Result: The pain score for the right knee joint after hand moxibustion was significantly different between the experimental group and the control group after hand moxibustion (p=.035). The pain score for the left knee joint was not significantly different between the experimental group and the control group after hand moxibustion (p=.075). Right and left knee ROM scores were significantly different between the experimental group and the control group after hand moxibustion (Right p=.000, Left p=.034). Discomfort of ADL score was not significantly different between the experimental group and the control group after hand moxibustion (p=.053). Conclusion: In summary, knee joint pain in elders after hand moxibustion decreased and knee ROM in elders after hand moxibustion increased. So it would be useful for nurses to provide hand moxibustion as an alternative therapy to elders with knee joint pain in the community and thus reduce joint pain and increase knee ROM.

• The Korean Journal of Pain
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• v.31 no.2
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• pp.87-92
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• 2018

Background: An epidural steroid injection (ESI) is a commonly administered procedure in pain clinics. An unintentional lumbar facet joint injection during interlaminar ESI was reported in a previous study, but there has not been much research on the characteristics of an unintentional lumbar facet joint injection. This study illustrated the imaging features of an unintentional lumbar facet joint injection during an interlaminar ESI and analyzed characteristics of patients who underwent this injection. Methods: From December 2015 to May 2017, we performed 662 lumbar ESIs and we identified 24 cases (21 patients) that underwent a lumbar facet joint injection. We gathered data contrast pattern, needle approach levels and directions, injected facet joint levels and directions, presence of lumbar spine disease as seen on magnetic resonance images (MRI), and histories of lumbar spine surgeries. Results: The contrast pattern in the facet joint has a sigmoid or ovoid contrast pattern confined to the vicinity of the facet joint. The incidence of unintentional lumbar facet joint injection was 3.6%. The mean age was 68.47 years. Among these 21 patients, 14 (66.7%) were injected in the facet joint ipsilaterally to the needle approach. Among the 20 patients who received MRI, all (100%) had central stenosis and 15 patients (75%) had severe stenosis. Conclusions: When the operator performs an interlaminar ESI on patients with central spinal stenosis, the contrast pattern on the fluoroscopy during interlaminar ESI should be carefully examined to distinguish between the epidural space and facet joint.

• Korean Journal of Child Studies
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• v.30 no.5
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• pp.155-165
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• 2009

This study was conducted to identify relationships between toddler-teacher joint attention and toddlers' vocabularies. Toddlers' vocabularies were assessed by the MacArthur Communicative Development Inventory-Korean (MCDI-K) modified by Kim (2006); joint attention episodes were observed by classification categories for engagement condition (Bakeman & Adamson, 1984). Data were analyzed by means, t-test and Pearson's correlations. Results were that : (1) receptive vocabulary of toddlers was about 1.1 times as high as their expressive vocabulary. (2) Coordinated joint attention was observed most frequently, followed by supported joint attention; coordinated joint attention was closely related to support joint attention. (3) The relationship between toddler-teacher joint attention and toddlers' vocabularies were significant in a positive direction.

• Journal of the Speleological Society of Korea
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• no.65
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• pp.1-10
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• 2004

Joint reflects the structure of the earth. And in many cases joints controls the developments of stream directions. In this studying area three joint sets are represented. One is concentrated to the north and the other is deviated $50^{circ}-60^{circ}$ from north to east and west. It is uncertain that the master joint set is a fault line, but the presence of the structural line is evident from the joint strike frequency. The Spearman's $\Upsilon$ between joint patterns and the stream directions is about 0.73.

• International Journal of Control, Automation, and Systems
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• v.4 no.4
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• pp.405-413
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• 2006

A novel approach based on genetic algorithms (GA) is developed to find a global minimum-jerk trajectory of a space robotic manipulator in joint space. The jerk, the third derivative of position of desired joint trajectory, adversely affects the efficiency of the control algorithms and stabilization of whole space robot system and therefore should be minimized. On the other hand, the importance of minimizing the jerk is to reduce the vibrations of manipulator. In this formulation, a global genetic-approach determines the trajectory by minimizing the maximum jerk in joint space. The planning procedure is performed with respect to all constraints, such as joint angle constraints, joint velocity constraints, joint angular acceleration and torque constraints, and so on. We use an genetic algorithm to search the optimal joint inter-knot parameters in order to realize the minimum jerk. These joint inter-knot parameters mainly include joint angle and joint angular velocities. The simulation result shows that GA-based minimum-jerk trajectory planning method has satisfactory performance and real significance in engineering.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.1
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• pp.9-16
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• 2013

This paper experimentally deals with the excitation by functional electrical stimulus(FES) and the response of electromyo-potential at the muscles of antebrachial joint in a human body. The excitation of FES, which results in the contraction of the muscles and thus the flection of the joint, shows that the flection angle of the joint is proportional to the magnitude of the stimulus current. The response of electromyo-potential measured according to the FES shows the linearly-proportional relation between the joint torque and the electromyo-potential. The results can be used for active motion of joint rehabilitation.

• International Journal of Safety
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• v.9 no.2
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• pp.16-21
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• 2010

In this study, the variations of transformed impact factors and load carrying capacity of highway bridges measured from the state of expansion joint are evaluated. the field loading tests were performed on the highway bridge with damaged expansion joint to investigate the variation of the load carrying capacity. From the field loading tests in case that damaged expansion joint exist or do not exist, the static displacements and dynamic displacements were measured, and TIF were calculated, respectively. dynamic test is performed in order to estimate dynamic displacement and TIF according to the level of damage of expansion joint. From the results of TIF, the load carrying capacity of highway bridges with damaged expansion joint were estimated.