• Journal of Korean Dental Science
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• v.17 no.1
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• pp.14-35
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• 2024

The temporomandibular joint (TMJ) is one of the most unique joints in the human body that orchestrates complex movements across different orthogonal planes and multiple axes of rotation. Comprising the articular eminence of the temporal bone and the condylar process of the mandible, the TMJ integrates five major ligaments, retrodiscal tissues, nerves, and blood and lymph systems to facilitate its function. Cooperation between the contralateral TMJ and masticatory muscles is essential for coordinated serial dynamic functions. During mouth opening, the TMJ exhibits a hinge movement, followed by gliding. The health of the masticatory system, which is intricately linked to chewing, energy intake, and communication, has become increasingly crucial with advancing age, exerting an impact on oral and systemic health and overall quality of life. For individuals to lead a healthy and pain-free life, a comprehensive understanding of the basic anatomy and functional aspects of the TMJ and masticatory muscles is imperative. Temporomandibular disorders (TMDs) encompass a spectrum of diseases and disorders associated with changes in the structure, function, or physiology of the TMJ and masticatory system. Functional and pathological alterations in the TMJ and masticatory muscles can be visualized using various imaging modalities, such as cone-beam computed tomography, magnetic resonance imaging, and bone scans. An exploration of potential pathophysiological mechanisms related to the TMJ anatomy contributes to a comprehensive understanding of TMD and informs targeted treatment strategies. Hence, this narrative review presents insights into the fundamental functional anatomy of the TMJ and pathological changes that evolve with TMD progression.

• Smart Media Journal
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• v.13 no.5
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• pp.9-18
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• 2024

Multi-Object trajectory modeling is a major challenge in MOT. CenterTrack tried to solve this problem with a Heatmap-based method that tracks the object center position. However, it showed limited performance when tracking objects with complex movements and nonlinearities. Considering the degradation factor of CenterTrack as the dynamic movement of pedestrians, we integrated the EKF into CenterTrack. To demonstrate the superiority of our proposed method, we applied the existing KF and UKF to CenterTrack and compared and evaluated it on various datasets. The experimental results confirmed that when EKF was integrated into CenterTrack, it achieved 73.7% MOTA, making it the most suitable filter for CenterTrack.

• Journal of Powder Materials
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• v.31 no.3
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• pp.213-219
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• 2024

Additive Manufacturing (AM) is a process that fabricates products by manufacturing materials according to a three-dimensional model. It has recently gained attention due to its environmental advantages, including reduced energy consumption and high material utilization rates. However, controlling defects such as melting issues and residual stress, which can occur during metal additive manufacturing, poses a challenge. The trial-and-error verification of these defects is both time-consuming and costly. Consequently, efforts have been made to develop phenomenological models that understand the influence of process variables on defects, and mechanical/ electrical/thermal properties of geometrically complex products. This paper introduces modeling techniques that can simulate the powder additive manufacturing process. The focus is on representative metal additive manufacturing processes such as Powder Bed Fusion (PBF), Direct Energy Deposition (DED), and Binder Jetting (BJ) method. To calculate thermal-stress history and the resulting deformations, modeling techniques based on Finite Element Method (FEM) are generally utilized. For simulating the movements and packing behavior of powders during powder classification, modeling techniques based on Discrete Element Method (DEM) are employed. Additionally, to simulate sintering and microstructural changes, techniques such as Monte Carlo (MC), Molecular Dynamics (MD), and Phase Field Modeling (PFM) are predominantly used.

• Journal of Distribution Science
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• v.22 no.8
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• pp.137-145
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• 2024

Purpose: This paper aims to reveal similarities and differences in behaviors in negative consumer-brand relationships. Thus, we focused on consumer motivation which includes intensity and direction of behaviors. The motivation for negative customer behavior has been discussed in the context of brand hate, but there is only limited research that has tried to measure it using quantitative methods. We are trying to measure customers' motivation in negative consumer-brand relationships and reveal the relationship between in-field customers' negative behaviors. Research design, data, and methodology: We adopt Reactive-Proactive aggression to measure the motivation of customers' behaviors in a negative consumer-brand relationship. Also, to reveal the relationship between in-field behavior and customer aggression, we survey Korean game communities to reactive-proactive aggression and behaviors, whether they participate, in each observed behavior during the serial negative consumer movements that occurred in the Korean game industry. As a methodology, we run multinomial logistic regression. Results: We observed 9 behaviors in this case, and we found that reactive-proactive aggression is related to participation and motivation of these behaviors. Conclusions: We suggest the potential of reactive-proactive aggression as motivation for customers' complex negative behaviors. Based on this potential, we hope reactive-proactive aggression could be used to reveal similarities and differences in behaviors in negative consumer-brand relationships.

• Journal of Distribution Science
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• v.22 no.8
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• pp.125-135
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• 2024

Purpose: This paper aims to reveal similarities and differences in behaviors in negative consumer-brand relationships. Thus, we focused on consumer motivation which includes intensity and direction of behaviors. The motivation for negative customer behavior has been discussed in the context of brand hate, but there is only limited research that has tried to measure it using quantitative methods. We are trying to measure customers' motivation in negative consumer-brand relationships and reveal the relationship between in-field customers' negative behaviors. Research design, data, and methodology: We adopt Reactive-Proactive aggression to measure the motivation of customers' behaviors in a negative consumer-brand relationship. Also, to reveal the relationship between in-field behavior and customer aggression, we survey Korean game communities to reactive-proactive aggression and behaviors, whether they participate, in each observed behavior during the serial negative consumer movements that occurred in the Korean game industry. As a methodology, we run multinomial logistic regression. Results: We observed 9 behaviors in this case, and we found that reactive-proactive aggression is related to participation and motivation of these behaviors. Conclusions: We suggest the potential of reactive-proactive aggression as motivation for customers' complex negative behaviors. Based on this potential, we hope reactive-proactive aggression could be used to reveal similarities and differences in behaviors in negative consumer-brand relationships.

• Journal of Oral Medicine and Pain
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• v.23 no.1
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• pp.21-36
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• 1998

The purpose of this study was analyse the mandibular movements in patients with internal derangement of the temporomandibular joint according to diagnostic subgroups. The author classified patients with internal derangement of the temporomandibular joint into 4 diagnostic subgroups by means of the magnet resonance imagings, and evaluated the clinical signs and the mandibular movements with Mandibular Kinesiograph(MKG) in each subgroups. The mandibular movements, measured in this study, were the types of movement in frontal and sagittal plane, velocities in opening and closing movement, and the opening and closing movement, and the opening and closing velocity pattern. The data were compared between the 5 groups including the normal group. The results were as follows : 1. Pain was more frequently observed in the anterior disc displacement without reduction group than in the anterior disc displacement with reduction group. Sound of joint was more frequently observed in the anterior disc displacement with reduction group, and limitation of mandibular opening movement was more frequently observed in the anterior disc displacement without reduction group. Duration of the anterior disc displacement without reduction group was significantly short compared to that of the anterior disc displacement with reduction group, and duration of the unilateral anterior disc displacement without reduction group was shortest in the experimental group. The frequency of Angle's classifications had not significant correlations between the experimental groups. 2. Active and passive range of the opening movement, maximum protrusive movement, maximum lateral movement toward left side were significantly decreased in the experimental groups compared to the control group, but there was no significant difference in the range of the maximum lateral movement toward right side between the control and experiment groups. In unilateral anterior disc displacement without reduction group, the range of maximum lateral movement toward unaffected side was no significant difference in the range of the maximum lateral movement between toward affected side and toward unaffected side. 3. Maximum opening velocity, maximum closing velocity, average opening velocity, average closing velocity and maximum velocity of terminal tooth contact were significantly decreased in the experimental groups compared to control group. There was no significant difference in maximum opening velocity and maximum velocity of Terminal tooth contact between the subgroups of the experimental group each other, but there was significant difference in maximum closing velocity, average opening velocity and average closing velocity between the subgroups each other. 4. In the frontal plane of the MKG, the frequency of complex deviation type(F-2)pattern was significantly increased in the anterior disc displacement with out reduction group compared to the anterior disc displacement with reduction group and the control group. In the sagittal plane, the frequency of coincident type(S-1)was decreased in the same group. 5. In the maximum opening velocity pattern, the frequency of no-peak type (OV-3)in the unilateral anterior disc displacement with reduction group was significantly increased compared to the control group. The frequency of 1-peak type (OV-1) and 2-peak type (OV-2) was decreased in the anterior disc displacement with out reduction group, but the frequency of no-peak type (OV-3)was increased in the same group. In the maximum closing velocity pattern, the frequency of no-peak type (CV-3) was significantly increased in the anterior disc displacement without reduction group. Compared to the anterior disc displacement with reduction group and the control group. The frequency of 1-peak type (CV-1) and 2-peak type (CV-2) in the anterior disc displacement with reduction group was decreased than that in the control group.

• The Journal of Art Theory & Practice
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• no.6
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• pp.27-50
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• 2008

This thesis examines contemporary Chinese painting after the Cultural Revolution(1966~76), focusing upon so-called "Chinese Pop art", which I termed as "Socialist Pop art". I considered the art of this period within the broader context of social changes especially after the Tienanmen incident of 1989. After the Cultural Revolution during which idolization of Chairman Mao was at its peak, one of the major changes in communist China was that an anti-Mao wave was generated in almost every social class. For example, novels that revealed the hardships during the Cultural Revolution were published. Posters that openly criticized the Maoism were also produced and displayed on the walls, and demand for democracy spurred widespread activist movements among young generations. These broad social changes were also reflected in art. A variety of art movements were introduced from the West to China, and after a period of experimentation with the new imported styles, artists began to apply the new artistic idiom to their works in order to visualize their own social and political realities they lived in. It was a shift from earlier Socialist Realism to a new expression either directly or indirectly, "Socialist Pop", an amalgam of Socialist Realism and Pop art tradition. After the 1989 crackdown of Tienanmen Square protest, when communist government quelled with brutal measures the students, workers, and ordinary people who rose for democracy, greater urge to protest the Deng Xiaoping regime emerged. This time coincided with the gradual emergence of art using Pop art vocabulary to satirize the social reality, the Socialist Pop art, along with many other art forms all with avant-garde spirit. One of the most frequent subjects of Chinese Pop art was visual images of Chairman Mao and his Cultural Revolution, and new China that was saturated with capitalism, which tainted the Chinese way of life with a Western way of consumerism and commercialism. The reason for the popularity of Mao's image was spurred by the "Mao Craze" in the early 1990's. People suddenly began to fall in a kind of nostalgia for the past, and once again, Mao Zedong was idolized as an entity who can heal the problems of modern China who had been marching towards their ultimate destination, the economic development. But this time Chairman Mao was no more an idol but just a popular, commercial product. He is no more an object of worship of almost religious nature but he has become an iconography symbolizing the complex nature of present Chinese society. During this process of depicting the social reality, Chinese artists are making the authority and sanctity of Maoism ineffective. Dealing with this new trend of contemporary Chinese art in view of "Socialist Pop art" two manners of re-creating Pop art can be illustrated: one that incorporates the propaganda posters of the Cultural Revolution; the other borrows from Chinese traditional popular imagery or mass media, such as photos taken during Mao era. What is worth mentioning is that these posters and photos of the Cultural Revolution can be identified as 'popular' media, as they were directed to educate the popular mass, thus combination of this ingenuous pop media with Western Pop art can be fully justified as a genre unique to China. Through this genre, we can discover a new chapter of the Chinese contemporary painting and its society, as their Pop art can be considered as self-portraits true to their present appearances.

• Science of Emotion and Sensibility
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• v.27 no.1
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• pp.59-68
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• 2024

This study aimed to develop a soft fabric-based elbow-bending angle sensor that can replace conventional hard-type inertial sensors and a system for estimating bending angles using it. To enhance comfort during exercise, this study treated four fabrics (Bergamo, E-band, span cushion, and polyester) by single-walled carbon nanotube dip coating to create conductive textiles. Subsequently, one fabric was selected based on performance evaluations, and an elbow flexion angle sensor was fabricated. Gauge factor, hysteresis, and sensing range were employed as performance evaluation metrics. The data obtained using the fabricated sensor showed different trends in sensor values for the changes in the angle during bending and extending movements. Because of this divergence, the two movements were separated, and this constituted the one-step process. In the two-step process, multilayer perceptron (MLP) was employed to handle the complex nonlinear relationships and achieve high data accuracy. Based on the results of this study, we anticipate effective utilization in various smart wearable and healthcare domains. Consequently, a soft- fabric bending angle sensor was developed, and using MLP, nonlinear relationships can be addressed, enabling angle estimation. Based on the results of this study, we anticipate the effective utilization of the developed system in smart wearables and healthcare.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.27 no.3
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• pp.239-249
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• 2001

The purpose of this study is to evaluate the relationship of the factors which could be influenced by orthognathic surgery especillay SSRO. We measured the amounts of the maximum opening, lateral movements, maximum velocity and pattern of mandibular path during the opening and closing of mandible at the following times ; preoperative, 1 month after operation, 6 months after operation respectively using MKG. And the results were compared according to the categorized subgroups. Following results were obtained : 1. The change of the amounts of mandibular lateral movement and maximum opening velocity were statistically different between male and female (p<0.05), but the others were not. 2. According to the method of operation, there was no difference in the change of the mandibular movements between the group of SSRO and SSRO plus LeFort I osteotomy (p>0.05). 3. According to the amounts of mandibular movement, the recovery of left lateral movement of the group of $6{\sim}10mm$ was better than the other groups (p<0.05). 4. In the frontal pattern of the opening and closing of the mandible, the complex deflected type (F5), simple deflected type (F4), complex deviated type (F3), simple deviated type (F2), straight type (F1) were obtained in order at the time of preoperative, simple deflected type, simple deviated type, complex deviated type, straight type, complex deflected type in order at the time of 1 month after surgery, and the result at the time of 6 months after surgery was the same with that of the time of preoperative. In the sagittal pattern, non-coincident type (S2) was predominant at the time of preoperative, and coincident type (S1) was predominant at the time of 1 month after surgery. After 6 months, the result was also the same with that of the preoperative in sagittal pattern. 5. There was not a statistical difference in the change of the mandibular movement between group of presence of the preoperative TMJ symptoms and non-presence group (p>0.05). 6. There was not a statistical difference in the change of the mandibular movement between repositioning device applied group and non-applied group (p>0.05). 7. Sixty three percents of the patients who had preoperative TMJ symptoms were improved after surgery and preoperative TMJ symptoms were more improved after operation in the repositioning device non-applied group statistically (p<0.05).

• Korean Journal of Applied Biomechanics
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• v.15 no.1
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• pp.45-61
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• 2005

Stance is defined as any state in which the total mass of the body is supported by the feet. In order to maintain stance, the sum of gravito-inertial forces acting on the body must be registered by equal and opposite forces at the region of contact between the organism and the support surface. Balance is controlled by applying forces to the surface of support so as to maintain the body's center of mass vertically above the feet. for a muIti-segment organism, there can be a variety of ways in which balance can be controlled, since movements of different body segments can have similar effects on the control of balance. In general, the organism tends to have a body configuration that is aligned with gravito-inertial force when there are no external forces acting on it. If any segments of the body are not aligned with gravito-inertial force vector, a torque on that segment would tend to move the body's center of mass. The maintenance of postural stability is accomplished in humans by a complex neural control system. This requires organizing integrating and acting upon visual, vestibular, and somatosensory input, providing orientation information to the postural control system. The information necessary to control and coordinate movement is provided by the visual sense of eye position with respect to the surrounding surface layout, the vestibular sense of head orientation in the gravito-inertial space, and the somatic sense of body segment position relative to one another and to the support surface. In this study, perception and action capability was examined from various points of view. The underlying assumption of the study was that the change of postural configuration could be effected by organism, environment and task goal.