• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.2
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• pp.169-178
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• 2010

Objective. This study was conducted to observe the effect on appendage muscle strength according to increase in occlusal vertical dimension. Materials and methods. Ten males with a mean age of 21 were selected. The tested occlusal splints were made at the position of increased occlusal vertical dimension of 2mm,3.5mm and 5mm from the intercuspal position. Before and after wearing occlusal splints, the appendage muscle strength were tested by Cybex II dynamometer (Lumex Inc., Ronkonkoma, NY, USA). Results. Statistical analysis using the paired t-test revealed significant differences for flexion and extension of the hip, pronation of the forearm, internal rotation of the shoulder, external and internal rotation of the knee, and dorsiflexion and plantarflexion of the ankle (p<0.05). Conclusions. As the result of this study, we conclude that when occlusal vertical dimension was increased, most of mean muscular strength values were increased. Especially at the position of 3.5mm increased vertical dimension displayed the highest mean muscular strength value than other positions.

• Korean Journal of Applied Biomechanics
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• v.16 no.1
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• pp.101-108
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• 2006

The purpose of this study was to compare GRF characteristics during walking wearing jogging and roller shoes. Twelve male middle school students (age: $15.0{\pm}0.0\;yrs$, height: $173.6{\pm}5.0\;cm$, weight: $587.6{\pm}89.3\;N$) who have no known musculoskeletal disorders were recruited as the subjects. Kinematic data from six S-VHS camcorders(Panasonic AG456, 60 fields/s) and GRF data from two force platform; (AMII OR6-5) were collected while subjects walked wearing roller and jogging shoes in random order at a speed of 1.1 m/s. An event sync unit with a bright LED light was used to synchronize the video and GRF recordings. GRF data were filtered using a 20 Hz low pass Butterworth. digital filter and further normalized to the subject's body weight. For each trial being analyzed, five critical instants and four phases were identified from the recording. Temporal parameters, GRFs, displacement of center of pressure (DCP), and loading and decay rates were determined for each trial. For each dependent variable, paired t-test was performed to test if significant difference existed between shoe conditions (p <.05). Vertical GRFs at heel contact increased and braking forces at the end of initial double limb stance reduced significantly when going from jogging shoe to roller shoe condition. Robbins and Waked (1997) reported that balance and vertical GRF are closely related It seems that the ankle and knee joints are locked in an awkward fashion at the heel contact to compensate for the imbalance. The DCP in the antero-posterior direction for the roller shoe condition was significantly less than the corresponding value for the jogging shoe condition. Because the subjects tried to keep their upper body weight in front of the hip to prevent falling backward, the DCP for the roller shoe condition was restricted The results indicate that walking with roller shoes had little effect on temporal parameters, and loading and decay rates. It seems that there are differences in GRF characteristics between roller shoe and jogging shoe conditions. The differences in GRF pattern may be caused primarily by the altered position of ankle, knee, and center of mass throughout the walking cycle. Future studies should examine muscle activation patterns and joint kinematics during walking with roller shoes.

• Korean Journal of Applied Biomechanics
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• v.19 no.2
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• pp.399-406
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• 2009

The purpose of this study was to compare the effect of wearing roller shoes and jogging shoes on kinematic characteristics in lower extremity during walking. Eight male middle school students(age: $15.0{\pm}0.0^{\circ}$ yrs, height $175.9{\pm}6.6cm$, weight: $616.3{\pm}84.9$ N) who have no musculoskeletal disorder were recruited as the subjects. Temporal parameters, step length, stride length, center of mass, velocity of CM, angle of segment, angular velocity and range of motion were determined for each trial. For each dependent variable, paired t-test was performed to test if significant difference existed between shoe conditions(p < .05). The results showed that stride length and velocity of CM in wearing roller shoes were significantly less than those found in wearing jogging shoes. These indicated that walking patterns may be changed by different shoe conditions and unstable braking condition because of wheel. Angle of ankle joint at LHC1 and LHC2 in wearing roller shoes was greater than the corresponding value for wearing jogging shoes. It seems that the ankle joints are locked in an awkward fashion at the heel contact to compensate for imbalance. Otherwise, dorsi flexion was not produced at the heel contact point in wearing roller shoes.

• Journal of Korea Technology Innovation Society
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• v.21 no.2
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• pp.875-905
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• 2018

Recently China's science and technology development is accelerating, and some technologies have the world's best technology. With the rapid development of science and technology, China has been deeply aware of the importance of science and technology, and many efforts are being made to legislate security regulations to protect their technologies. Korea and other countries are also interested in research security, and research and development cooperation with China is also on the rise. In this paper, we derived some implications by comparing and analyzing China's science and technology security regulation and Korea's national R&D project management regulations. China is also enacting science and technology security regulations as a subordinate to the laws and regulations of science and technology. However, it should be reflected in future legislation that the difference from Korea is composed of separate independent regulations. In particular, the fact that the science and technology security regulations have been enacted separately may be a hint that can be reflected in the nation's future legislation processes. In this paper, major contents of the science and technology security regulations, points to division of knowledge property into scientific and technological cooperation or security tasks, designation of regulations on the characteristics of research security guidelines, and operation of individual national security agencies In addition, in the event that the contents of the related statutes, confidentiality provisions, and import and import control are recorded in this paper, and the results of the joint R&D project are not utilized, or the technology transfer is not carried out.

• The Journal of Korean Academy of Prosthodontics
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• v.24 no.1
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• pp.17-26
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• 1986

The purpose of this study was to investigate true hinge axis location with different times (8:00-9:00 A.M.,2:00-3:00 P.M.) and with experienced and inexperienced groups. 25 subjects, 23-27 years of age , with functionally acceptable occlusion, and no clinical signs of temporomandibular joint dysfunction were participated in this study. In this study arbitrary hinge axis point was located 13 mm anterior to the posterior margin of the tragus on a line from the center of the tragus to the outer canthus of the eye and then the true hinge axis point was located with T.M.J. hinge axis locator. The discrepancies of distance and the direction between true hinge axis point and arbitrary hinge axis point were studied according to times and two groups. The results obtained were as follows : 1. The mean distance from arbitrary hinge axis point to the true hinge axis point on the right and left sides was as follows : Experienced group: linear distance: $1.228{\pm}3.145mm$, vertical distance: $-1.128{\pm}2.515mm$, horizontal distance: $-0.484{\pm}1.806mm$. Inexperience group: linear distance: $1.628{\pm}3.158mm$, vertical distance: $-1.169{\pm}2.090mm$, horizontal distance: $-1.133{\pm}2.367mm$. Horizontal distance between experienced and inexperienced groups was significant statistically. (P<0.1) 2. True hinge axis points located within 5 mm of arbitrary hinge axis point were 86.7% in the experienced group and 84% in the inexperienced group. 3. For experienced operator A with time, the mean distance from arbitrary hinge axis point to true hinge axis point was as follows: Horizontal distance: AM: $-0.613{\pm}1.966mm$, PM: $-0.860{\pm}2.156mm$. Vertical distance: AM: $-0.886{\pm}2.518mm$, PM : $-1.226{\pm}2.660mm$. True hinge axis points had tendency to be located posterior-inferiorly to tragus-canthus line in the afternoon than in the morning, but there was not significant statistically. (P>0.1)

• Journal of Acupuncture Research
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• v.22 no.2
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• pp.93-101
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• 2005

Objective: We have evaluated UDHA into the joint for its effectiveness on immune responses to CII in the rat CIA. In an attempt to gain further insight into the mode of action of UDHA, we also investigated the effects of UDHA on the incidence and development of arthritis in rat CIA with 2 different regimens: (1) started prior to a primary immunization, (2) started on the day of a primary immunization. Methods : Male rats were immunized with an emulsion of $200\;{\mu}g/100g$ of CII and complete Freund's adjuvant (CFA). The rats were then given intraperitoneal(i.p) stimulation of Ulmus davidiana Planch herbal acupuncture(UDHA) or saline during the experiment. Lymph node cells were obtained from rats 14 days after immunization and cultured in vitro with CII. When compared with rats treated with saline as control, UDHA at doses of more than $20\;{\mu}g/100\;g$ rat once a day for 7 days inhibited the ability of inguinal lymph node cells to produce T cell cytokines interleukin-$1{\beta}$, tumor necrosis $factor-{\alpha}$ $(TNF-{\alpha})$. When rats were injected intraperitoneally with SRBC, hemaglutination titers in UD-treated and control rats did not differ significantly when low doses of UD was given to rats. However, i.p injection of UD at doses of more than $10\;{\mu}g/100\;g/day$ for 7 days slightly suppressed antibody production. Results : The present results show that treatment with UDHA can inhibit the onset and development of arthritis and the immune responses to collagen. Conclusion: Therapeutic i.p injection with UD affect the clinical course of the disease and the immune responses to CII.

• The Journal of the Korean bone and joint tumor society
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• v.12 no.2
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• pp.112-117
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• 2006

Purpose: The purpose of this study was to investigate on primary bone tumors of fibula. Materials and Methods: Patients who received operative treatment from January 1993 to December 2005 for primary bone tumors of fibula were analyzed for clinical outcomes. Results: There were 17 patients(10 males, 7 females) who were diagnosed for primary bone tumors of fibula. Osteochondroma was the most common diagnosis and others were osteosarcoma, fibrous dysplasia. The malignant bone tumors were 10.5% of all fibula tumors. There were 12 cases on proximal, 4 cases on mid shaft, and 1 cases on distal part of fibula. At the final follow up, 14 patients reported patient satisfaction of either excellent or good. Conclusion: Bone tumor of fibula doesn't need reconstruction after the resection unless it invades tibia or its site distal, which enables easy surgical resection. However, generally it is rare and accompany with vague symptoms, so careful approach to diagnosis is necessary because late diagnosis can mean the needs for amputation.

• Archives of design research
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• v.17 no.1
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• pp.319-328
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• 2004

The communication environment made by digital technologies has made it possible to exchange information and deliver messages fast and easily among people of various classes in virtual space beyond time and space. Net-generation, who is accustomed to this virtual space, couldn't be satisfied with the linear text-oriented language any more, and began to make signs by use of computers in order to differentiate itself from others and to express its desires. Among the signs, emoticon created by joint of popular culture and digital communication centering around young generation is a new visual sign and emotional sign that can deliver a sender's feelings contained in a message. This paper has studied social phenomena, their relationships with emoticon and background of its creation through documentary review of media development, changes in the communication environment and popular culture. Furthermore, it has analyzed the meaningful action and roles of emoticon as a sign in terms of semiotics and also, studied a possibility of using emoticon as a new emotional sign. The study results say that emoticon can play the roles of a non-linguistic sign just like general signs that make mutual exchange through meaningful action, and also that it can be used to effectively deliver messages not only in virtual space, but also in advertising, posters, magazines and CI. However, emoticon is better at emotional expressions yet than other textual signs or visual signs, but in order to position itself as a universal and popular sign, emotional expressions should be clear, any difference in understanding messages should be removed, and message delivery should be more efficient.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.2
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• pp.105-114
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• 2018

Modular system can be divided into two types based on the methods of resisting load. The one is the open-sided modular system composed of beams and columns. The other is the enclosed modular system composed of panels and studs. Of the Modular systems, the use of open-sided modular system is limited because it consists of closed member sections. In order to solve this problem, Choi et al.(2017) proposed a composite modular system with folded steel members filled with concrete. However, it was assumed in the previous study that the connections between modules are composed of rigid joint. Therefore it didn't identify the effect of connection behavior in structure. This study used finite element analysis to calculate stiffness of the connections in the proposed modular system. The linearization method presented in FEMA 440 is used for seismic performance assessment of structures, considering the connection stiffness computed in this study. The result of analysis shows that the capacity and story drift ratio obtained in the model considering stiffness of connection are less than those in the model not considering connection stiffness. Based on this observation, it is concluded that the stiffness of connection has a considerable effect on structural behavior.

• Tunnel and Underground Space
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• v.15 no.2 s.55
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• pp.119-128
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• 2005

Although the evaluation of the mechanical properties and behavior of jointed rock masses is very important for the design of tunnel and underground openings, it has always been considered the most difficult problem. One of the difficulties in describing the rock mass behavior is the selection of the appropriate constitutive model. This limitation may be overcome with the progress in discrete element software such as PFC, which does not need the user to prescribe a constitutive model for rock mass. In this paper, a 30\;m\;\times\;30\;m\;\times\;30\;m m jointed rock mass of road tunnel site was analyzed. h discrete fracture network was developed from the joint geometry obtained from core logging and surface survey. Using the discontinuities geometry from the DFN model, PFC simulations were carried out, starting with the intact rock and systematically adding the joints and the stress-strain response was recorded for each case. With the stress-strain response curves, the mechanical properties of jointed rock masses were determined. As expected, the presence of joints had a pronounced effect on mechanical properties of the rock mass. More importantly, getting the mechanical response of the PFC model doesn't require a user specified constitutive model.