• Journal of Oral Medicine and Pain
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• v.26 no.1
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• pp.59-73
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• 2001

This study was performed to investigate the effects of occlusal appliance on the mandibular position and the mandibular rotational torque movement during speech. For this study, 20 patients with temporomandibular disorders(TMDs) and 20 normal subjects without any signs and symptoms in the masticatory system were selected as the patient group and as the normal group, respectively. Biopak $system^{(R)}$(Bioresearch Inc., Milwaukee, USA) and a sentence of 'Sue is missing her house' were used for recording and for observing of speech pattern. There were five mandibular positions observed in this study, that is, mandibular rest position, 'ssi', 'her', 'ha', and 's' speech position. In each position, slant and A-P distance in sagittal plane, vertical distance and lateral distance in frontal plane were measured. Amount of the mandibular rotational torque movement were measured at 'her', 'ha' speech position and for all through speech movement. Centric relation splint(CRS) was placed in both groups, but anterior or posterior bite plane were placed in normal subjects only. Data collected were processed and analysed by SPSS windows program. The results of this study were as follows : 1. Mandibular positions in both groups were not different before adaptation, with CRS, and after removal, but total amount of the mandibular rotational torque movement was greater in patients. 2. Mandible was slightly placed anteriorly with CRS at 'her' and 'ha' speech position in patients, but was placed anteriorly at all the five positions in normal subjects. 3. Difference with type of occlusal appliance in normal subjects were noted only for vertical distance at 'ssi' and 'ha' speech position, and the distance with CRS were more than that with posterior bite plane. 4. Mandibular rotational torque movement at 'her' and 'ha' speech position was greater in patients, but the difference was disappeared after appliance removal. And the torque movement was greater at 'ha' speech position than that at 'her' speech position in frontal plane. It could be concluded that the adaptation of occlusal appliance showed a tendency to locate the mandible anteriorly during speech in both groups, but did not affect total mandibular rotational torque movement which was greater in patients.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.2
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• pp.79-88
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• 2004

Gaze detection is to locate the position on a monitor screen where a user is looking by computer vision. Gaze detection systems have numerous fields of application. They are applicable to the man-machine interface for helping the handicapped to use computers and the view control in three dimensional simulation programs. In our work, we implement it with a computer vision system setting a IR-LED based single camera. To detect the gaze position, we locate facial features, which is effectively performed with IR-LED based camera and SVM(Support Vector Machine). When a user gazes at a position of monitor, we can compute the 3D positions of those features based on 3D rotation and translation estimation and affine transform. Finally, the gaze position by the facial movements is computed from the normal vector of the plane determined by those computed 3D positions of features. In addition, we use a trained neural network to detect the gaze position by eye's movement. As experimental results, we can obtain the facial and eye gaze position on a monitor and the gaze position accuracy between the computed positions and the real ones is about 4.8 cm of RMS error.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.5 no.2
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• pp.169-180
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• 2010

Objectives: This study was carried out to investigate the relationship of leg length analysis and X-ray finding according to positions and valuation bases on diagnosis of pelvic malpositions. Methods: Twenty-two people who get $33.09{\pm}10.73$ as average were evaluated by leg length analysis and X-ray findings. After measuring innominate measurement(IM), femur head line. distance between S2 and posterior superior iliac spine(PSIS). ilium shadow measurement(ISM), major axis of obturator foramen(MaF), minor axis of obturator foramen(MiF) and distance between off centering measurement and symphysis pubis, those were analyzed. Results: 1. In assessment of posterior rotation malposition ilium(PI), it was showed the best coincidence between leg length analysis and X-ray analyzed by 1M in supine position(11 cases, 50.5%). 2. In assessment of inflare, coincidence index between leg length analysis and X-ray were not good($4.00{\pm}3.03$ cases, $18.15{\pm}13.82%$). And leg length analysis were not sensitive. 3. On the whole, coincidence index between leg length analysis and X-ray were not good(best: 1 case, 45.5%; worst: 11 cases, 50.0%). Conclusions: Results form this investigation showed the relationship of leg length analysis and X-ray according 10 positions and valuation bases on diagnosis of pelvic malpositions. This results are expected to contribute to establish method of assessment in diagnosis of pelvic malpositions.

• Physical Therapy Korea
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• v.24 no.2
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• pp.1-8
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• 2017

Background: Individuals with spinal cord injury (SCI) rely on their upper limbs for body-lifting activity (BLA). While studies have examined the electromyography (EMG) and kinematics of the shoulder joints during BLA, no studies have considered foot position during BLA. Objects: This study compared the effects of different foot positions during BLA on the shoulder muscle activities, peak plantar pressure, knee flexion angle, and rating perceived exertion in individuals with SCI. Methods: The study enrolled 13 mens with motor-complete paraplegic SCI, ASIA (American Spinal Injury Association) A or B. All subjects performed BLA with the feet positioned on the wheelchair footrest and on the floor independently. Surface EMG was used to collect data from the latissimus dorsi, pectoralis major, serratus anterior, and triceps brachii. The peak plantar pressure was measured using pedar-X and the knee flexion angle with Image J. Borg's rating perceived exertion scale was used to measure the physical activity intensity level. The paired t-test was used to compare the shoulder muscle activities, peak plantar pressure, knee flexion angle, and rating perceived exertion between the two feet positions during BLA. Results: The activity of the latissimus dorsi, pectoralis major, serratus anterior, and triceps brachii and rating perceived exertion decreased significantly and the peak plantar pressure and knee flexion angle increased significantly when performing BLA with the feet positioned on the wheelchair footrest compared with on the floor (p<.05). Conclusion: These findings suggest that individuals with SCI may perform BLA with the feet positioned on the wheelchair footrest for weight-relief lifting to decrease the shoulder muscle activities and the rating perceived exertion and to increase the peak plantar pressure and the knee flexion angle.

• Journal of Periodontal and Implant Science
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• v.31 no.3
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• pp.641-649
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• 2001

The aim of present study was to assess the thickness of masticatory mucosa on the hard palate and tuberosity as a potential donor site for mucogingival surgery. Thickness measurement was performed in 30 dental college students who are periodontally healthy, with a recently developed, ultrasonic device(SDM). The mean age of study subjects was 23.7(range 21-29) years old and the subjects were composed of 18 males and 12 females. Eighteen standard measurement points were defined on the hard palate, located on 3 lines which ran at different distances parallel to the gingival margin. Six positions were designated on each of these 3 lines between the level of the canine and the second molar. On the tuberosity, 6 standard measurement points were defined, located on 2 lines running parallel to the gingival margin at different distances. Data were analyzed to determine differences in gender, between different positions, and between lines, by an analysis of variance. The results showed that the mucosa of the tuberosity was significantly thicker than that of the hard palate region. Gender did not influence the thickness of masticatory mucosa, either on the hard palate or the tuberosity. On the hard palate, mucosa thickness increased as the distance from the marginal gingiva increased. The mucosa over the palatal root of the maxillary first molar was significantly thinner than that at all other positions on the hard palate. Measurement error at palate was 0.25mm, at tuberosity 0.51mm. No difference in the thickness of masticatory mucosa on palate and tuberosity was found between men and women. On the hard palate, soft tissue thickness progressively increased in sites further from the gingival margin. Therefore, we may harvest more thicker graft on the tuberosity that has more masticatory mucosa thickness than hard palate, however the width may not be sufficient for using.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.2
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• pp.193-200
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• 2008

Statement of problem: There have been a few studies about unsplinted implant retainted maxillary overdenture. Purpose: The purpose of this study was to examine the effect of different position of implant for 2 implants-retained maxillary overdenture. Materials and methods: Three-dimensional finite element models were used to reproduce an edentulous human maxilla with an implant-retained overdenture. Two implants in the canine tooth positions on both side and in the second premolar tooth positions on both side models were examined. Axial loads of 100 N were applied to the occlusal surface at the right first molar tooth positions. Maximum stress at the implant-bone interface and stress at the cortical bone surface just under the loading point were observed. Results and conclusion: Within the limits of this study, maximum stresses were concentrated around implant of canine position at loading side. The second premolar area was thought to be more favorable to distribution of stress on mucosa, alveolar bone and implants than canine area for maxillary overdenture.

• Journal of the Korea Concrete Institute
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• v.20 no.2
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• pp.165-173
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• 2008

One of the most important requirements for reinforced concrete constructions is the bond behavior between concrete and reinforcement. For practical application, it is very important to study bond behavior of reinforcing bars in recycled aggregate concrete (RAC). Thirty six pull-out tests were carried out in order to investigate the bond behaviour between recycled coarse aggregate concrete (RCAC) and deformed bars. RCA replacement ratios (i.e., 0%, 30%, 60% and 100%) and positions of deformed bar (i.e., vertical and horizontal position) were considered as variables in this paper. Each specimen was in the form of a cube, with edges of 150 mm in length and for the pull-out tests, a deformed bar, 13 mm in diameter, was embedded in the center of each specimen. Based on the test results, the bond strength between the RCAC and deformed bars were influenced by both RCA replacement ratios and positions of deformed bars. It was found that under the equivalent mix proportion (i.e., the mix proportions are the same, except for different RCA replacement ratios), the bond strength between the RCAC and the ribbed bar has no obvious relation with the RCA replacement ratio, whereas the positions of deformed bars have a significant effect on the bond behavior between the RCAC and deformed bars. Under the condition of same RCA replacement ratio, the specimen of horizontal reinforcement at upper position (HU type) appear considerably low bond stress.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.808-814
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• 2010

In this paper we executed a SBL(Short Baseline) underwater acoustic positioning system that is a kind of underwater position estimation system to estimates the 3-dimensional position of ROV(Remotely Operated Vehicle) using hydrophones and DAQ(Data Acquisition) system in the basin which dimensions are $3{\times}3{\times}1.7(m)$. For this experiment, we let 4 hydrophones in different positions of the basin for receiver and 1 hydrophone is fixed on the underwater vehicle for transmitting sensor(pinger). These five hydrophones are communicated with each other to find the 3-D positions of the moving ROV in the basin. The measured signals are collected by DAQ system and the positions of the ROV are plotted by LabView program in real-time. To estimate the position of the ROV we used a trigonometric method. In X and Y plane the estimated data has a small errors but in Z plane the estimated data has large errors so we cannot use this data for position control. One solution of this problem is using depth sensor that implemented of the underwater vehicle. Hereafter, we will test in the ocean using designed SBL system.

• The KIPS Transactions:PartD
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• v.12D no.5 s.101
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• pp.699-708
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• 2005

It becomes easy and generalized to track the cellular phone users and vehicles according to the Progress of wireless telecommunication, the spread of network, and the miniaturization of terminal devices. It has been constantly studied to provide location based services to furnish suitable services depending on the positions of customers. Various vehicle tracking and management systems are developed to utilize and manage the vehicle locations to relieve the congestion of traffic and to smooth transportation. However the designed previous work can not evaluated in real world, because most of previous work is only designed not implemented and it is developed for simple model to handle a point, a line, a polygon object. Therefore, we design a moving object query language and implement a vehicle management system to search the positions and trajectories of vehicles and to analyze the cost of transportation effectively. The designed query language based on a SQL can be utilized to get the trajectories between two specific places, the departure time, the arrival time of vehicles, and the predicted uncertainty positions, etc. In addition, the proposed moving object query language for managing transportation vehicles is useful to analyze the cost of trajectories in a variety of moving object management system containing transportation.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.3
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• pp.257-264
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• 2012

Objectives: This study's aims were to evaluate the effects of load center of gravity within an object lifted and feet placements on peak EMG amplitude acting on bilateral low back muscle groups, and to suggest adequate foot strategies with an aim to reducing low back pain incidence while lifting asymmetric load. Methods: The hypotheses that asymmetric load imposes more peak EMG amplitude on low back muscles contralateral to load center of gravity than symmetric load and maximum peak EMG amplitude out of bilateral ones can be relieved by locating one foot close to load center of gravity in front of the other were established based on biomechanics including safety margin model and previous researches. 11 male subjects were required to lift symmetrically a 15.8kg object during 2sec according to each conditions; symmetric load-parallel feet (SP), asymmetric load-parallel feet (AP), asymmetric load-one foot contralateral to load center of gravity in front of the other (AL), and asymmetric load-one foot ipsilateral to load center of gravity in front of the other (AR). Bilateral longissimus, iliocostalis, and multifidus on right and left low back area were selected as target muscles, and asymmetric load had load center of gravity 10cm deviated to the right from the center in the frontal plane. Results: Greater peak EMG amplitude in left muscle group than in right one was observed due to the effect of load center of gravity, and mean peak EMG amplitudes on both sides was not affected by load center of gravity because of EMG balancing effect. However, the difference of peak EMG amplitudes between both sides was significantly affected by it. Maximum peak EMG amplitude out of both sides and the difference of peak EMG amplitude between both sides could be reduced with keeping one foot ipsilateral to load center of gravity in front of the other while lifting asymmetric load. Conclusions: It was likely that asymmetric load lead to the elevated incidence of low back pain in comparison with symmetric load based on maximum peak EMG amplitude occurrence and greater imbalanced peak EMG amplitude between both sides. Changing feet positions according to the location of load center of gravity was suggested as one intervention able to reduce the low back pain incidence.