• Journal of Oral Medicine and Pain
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• v.22 no.1
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• pp.167-181
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• 1997

The aim of this study was to investigate the relationship between velocity and factors which could affect the velocity of mandibular movement. For this study, 30 dental students without any masticatory signs and symptoms and 90 patients with temporomandibular disorders(TMD) were selected as the control group and the patients group, respectively. After determining Angle's classification and lateral guidance pattern of occlusion, clinical examination for TMD was perfomed. Velocity and distance of mandibular movements were recorded with BioEGN, reproducibility index of lateral excursions was evaluated by Pantronic(PRI) and BioEGN (BERI) activity in masticatory and cervical muscles were measured with BioEMG, and occlusal contact time and cross-arch unbalance(Total left-right statistics, TLR) on clenching were recorded with T-scan, respectively. The results of this study were as follows : 1. Velocity in the patients was faster than that in the controls in most mandibular movements, but on wide opening and closing movement, result was reverse. 2. Velocity on closing movements were faster than that on opening movements in the control group and a similar tendency was also shown in the patients group. 3. Patients with muscle disorders showed a tendency to have the highest value of velocity of all diagnostic subgroups, while patients with degenerative joint diseases showed a tendency to have the lowest value. 4. Patients with canine guidance showed a tendency to have the highest value of velocity in three subgroups by lateral guidance pattern, while patients with group function showed a tendency to have the lowest value. 5. BERI had a positive correlation with opening velocity on lateral excursion, while TLR had a negative correlation with opening velocity on swallowing. 6. EMG activity on clenching in masticatory muscles had negative correlation with opening velocity on border movements, and on swollowing, while the activity in rest correlated positively with opening velocity on border movements. 7. There were positive correlation between the velocity and the distance in long components of mandibular trajectory.

• The korean journal of orthodontics
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• v.49 no.3
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• pp.188-193
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• 2019

Objective: The aim of this finite element study was to clarify the mechanics of tooth movement in palatal en-masse retraction of segmented maxillary anterior teeth by using anchor screws and lever arms. Methods: A three-dimensional finite element method was used to simulate overall orthodontic tooth movements. The line of action of the force was varied by changing both the lever arm height and anchor screw position. Results: When the line of action of the force passed through the center of resistance (CR), the anterior teeth showed translation. However, when the line of action was not perpendicular to the long axis of the anterior teeth, the anterior teeth moved bodily with an unexpected intrusion even though the force was transmitted horizontally. To move the anterior teeth bodily without intrusion and extrusion, a downward force passing through the CR was necessary. When the line of action of the force passed apical to the CR, the anterior teeth tipped counterclockwise during retraction, and when the line of action of the force passed coronal to the CR, the anterior teeth tipped clockwise during retraction. Conclusions: The movement pattern of the anterior teeth changed depending on the combination of lever arm height and anchor screw position. However, this pattern may be unpredictable in clinical settings because the movement direction is not always equal to the force direction.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.15 no.2
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• pp.81-94
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• 2005

Recently, wireless LAN circumstance is being widely deployed in Public spots. Many People use Portable equipments such as PDA and laptop computer for multimedia applications, and also demand of mobility support is increasing. However, handoff latency is inevitably occurred between both APs when clients move from one AP to another. To reduce handoff latency. in this paper, we suggest WFH(Weighted Frequent Handoff) using effective data structure. WFH improves cache hit ratio using a new cache replacement algorithm considering the movement pattern of users. It also reduces unessential duplicate traffics. Our algorithm uses FHR(Frequent Handoff Region) that can change pre-authentication lesion according to QoS based user level, movement Pattern and Neighbor Graph that dynamically captures network movement topology.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.2
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• pp.132-138
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• 1997

Six different types of velocity profiles of trolley movement of a container crane are investigated for the minimal sway angle at the target trolley position. Three velocity patterns which include trapezoidal, stepped and notched-type velocity patterns are obtained assuming constant rope length. The notched type velocity pattern is shown to be derived from the time-optimal bang-bang control. The stepped type velocity pattern can be shown to be derived as bang-off bang control as well. Considering the damping effect due to hoist motion a double stage acceleration pattern is also analyzed. The main objective of the paper is to show how much time-reduction can be obtained among several velocity patterns appearing in the literature.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.4
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• pp.307-314
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• 2006

In this paper, we present a comprehensive study for the development of quadruped walking robot. To understand the walking posture of a tetrapod animal, we begin with a careful observation on the skeletal system of tertapod animals. From taking a side view of their skeletal system, it is noted that their fore limbs and hind limbs perform characteristic roles during walking. Moreover, the widths of footprints and energy efficiency in walking have a close relationship through taking a front view of their walking posture. According to these observations, we present a control method where the kinematical solutions are not necessary because we develop a new rhythmic gait pattern for the quadruped walking robot. Though the proposed control method and rhythmic pattern are simple, they can provide the suitable motion planning for the robot since the resultant movement is based on the animal's movements. The validity of the proposed idea is demonstrated through dynamic simulations.

• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.621-630
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• 1994

The purpose of this study was to evaluate root resorption and alveolar bone resorption pattern by jiggling movement. 16 adult cats were divided into 4 groups(6, 12, 18, 24 days). In test side, mesio-distal jiggling force was applied in right maxillary 1st premolar in 3 days cycle In control side, mesial force was applied in left maxillary 1st premolar. Radiographic and histologic observation were performed in 6, 12, 18, 24 days after force application. The results were as follow: 1. Alveolar bone resorption was more severe by jiggling force than by unidirectional force. 2. Root resorption pattern was not different between jiggling force and unidirectional force. 3. Combined pattern of bone resorption and new bone formation appeared in jiggling group. 4. New bone formation began to appear at periapical area of jiggling group after 24 days, because alveolar bone resorption was severe and extrusion resulted.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.229-232
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• 2005

Many kinds of communication systems will be co-existed in the next generation communication environment. Location management will be one of the most important strategies in the future communication network. Whether the user gets the service in any kind of communication system, it is required to know the location of the user properly and manages this location information efficiently. In this paper, mobile IP and WCDMA systems are considered as next generation communication systems. We improve the performance of communication in heterogeneous networks adjusting the conventional region-based location management strategy in homogeneous network. This strategy can be adjusted dynamically to the communication system on the basis of packet-to-mobility ratio (PMR) in mobile IP system or call-to-mobility ratio (CMR) in WCDMA system, lots of different system parameters, and movement pattern of the user. This can be also based on the performance analysis with considering signaling cost and database access cost.

• Journal of Korean Society of Transportation
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• v.8 no.2
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• pp.55-66
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• 1990

The research deals with the establishment of transportation areas in the metropolitan cities. The purpose is three-fold ; 1) to review the existing literature : 2) to analyze the commuting (work and school) pattern and interregional movement pattern of passengers and freights ; 3) to establish the metropolitan transportation area based on the above analyses. The transportation area is defined by the analysis of trip pattern to the center city of each metropolitan area. The detailed indices for establishment are selected by the rank-size and time-distance analyses. For the operational purpose, the study defines 3 different transportation areas as follows : the first transportation area means the directly effecting region of the center city ; the second means the region with many reverse trips and development potentials ; and the third means the indirectly effecting region. It can be concluded that the first transportation area includes 10 cities and 5 counties in Seoul metropol tan region, Yangdsan-Gun, Kimhae-Gun and Kimhae-Si in Busan, Dalsung-Gun, Chilgok-Gun and Kyungsan-Gun in Daegu, Hwasung-Gun and Raju-Gun in Kwangju, and Daeduk-Gun in Daejun. These results could be expected to have many implications for the establishment of area-wide public transportation network, the metropolitan transportation decision-making bodies and others.

• Journal of Electrical Engineering and Technology
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• v.10 no.6
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• pp.2368-2375
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• 2015

To accommodate various navigational commands, a humanoid should be able to change its walking motion in real time. Using the modifiable walking pattern generation (MWPG) algorithm, a humanoid can handle dynamic walking commands by changing its walking period, step length, and direction independently. If the humanoid is given a command to perform an infeasible movement, the algorithm substitutes the infeasible command with a feasible one using binary search. The feasible navigational command is subsequently translated into the desired center-of-mass (CM) state. Every sample time CM reference is generated using a zero-moment-point (ZMP) variation scheme. Based on this algorithm, various complex walking patterns can be generated, including backward and sideways walking, without detailed consideration of the feasibility of the navigational commands. In a previous study, the effectiveness of the MWPG algorithm was verified by dynamic simulation. This paper presents experimental results obtained using the small-sized humanoid robot platform DARwIn-OP.

• Korean Management Science Review
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• v.23 no.3
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• pp.63-75
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• 2006

There are many kinds of research on web graph, most of them are focus on the hyperlinked structure of the web graph. Well known results on the web graph are rich-get-richer phenomenon, small-world phenomenon, scale-free network, etc. In this paper, we define 3 new directed web graph, so called the Web Usage Pattern Graph (WUPG), that nodes represent web sites arid arcs between nodes represent a movement between two sites by users' browsing behavior. The data to constructing the WUPG, approximately 56,000 records, are gathered from some users' PCs. The results analysing the data summarized as follows : (i) extremely rich-get-richer phenomenon (ii) average path length between sites is significantly less than the previous one (iii) less external hyperlinks, more internal hyperlinks.