• Journal of Korean Physical Therapy Science
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• v.29 no.1
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• pp.64-72
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• 2022

Background: The purpose of this study is to investigate the effect of wall squat exercise according to the difference in the support surface on the thickness change of external oblique, internal oblique and transverse abdominalis of the trunk muscles and the change in distance of center of pressure when the eyes are opened and closed. Design: Randomized controlled trial. Methods: The subjects were 26 healthy adults, 18 males and 8 females. The composition of each group using the single-blind method was 13 people in the unstable side wall squat exercise group and 13 people in the stable side wall squat exercise group. Experimental measurements were divided into before, 3 weeks, and 6 weeks after the experiment, and changes in muscle thickness and balance were confirmed. Muscle thickness was measured using ultrasinic, and static balance change was measured using Bio-rescue. Results: There were significant differences in the thickness changes of external oblique, internal oblique and transverse abdominalis according to the wall squat exercise method by period and in the interaction between the period and the group (p<0.05). As a result of the post-hoc analysis, there was a significant difference in the change between the two groups in external oblique muscle after 6 weeks. And there was a significant difference in the distance of the pressure center between eyes open and closed eyes (p<0.05). Conclusion: In terms of instability, wall squat exercise was positive for changes in trunk muscle thickness. It suggests the possibility of using it for trunk muscle strengthening training in the future.

• Journal of Platform Technology
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• v.10 no.2
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• pp.10-19
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• 2022

Moving assistant devices for people who are difficult to move are becoming electric-powered and automated. These moving assistant devices are not suitable for moving stairs at which the height between floor surfaces is different because these devices are designed and manufactured for flatland moving. An electric-powered and automated moving assistant device should change direction or stop when it approaches stairs in a movement direction. If the user or automatic control system does not change direction or stop in time, a moving assistant device can roll over or collide with stairs. In this paper, we propose a stairs detection method by using oblique distance measured by one sensor tilted to flatland. The method proposed in this paper can detect upward or downward stairs by using a difference between a predicted and measured oblique distance in considering a tilted angle of a sensor for measuring an oblique distance and installation height of the sensor on a moving object. Before the device enters a stairs region, if our proposed method provides information about detected stairs to a device's controller, the controller can do adequate action to avoid the accident.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.3
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• pp.158-166
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• 2019

Objectives: Inferior alveolar nerve block (IANB) is the most frequently used treatment for mandibular molars. Successful IANB requires insertion of the dental needle near the mandibular foramen. In this study, we aimed to analyze the anatomic location of the mandibular lingula and evaluate the effects of internal oblique ridge (IOR)-guided IANB. Materials and Methods: The location of the mandibular lingula was measured using cone-beam computed tomography images of the mandibles obtained from 125 patients. We measured the distances from the occlusal plane to the lingula and from the IOR to the lingula in 250 mandibular rami. Based on the mean of these distances, alternative anesthesia was carried out on 300 patients, and the success rate of the technique was evaluated. Results: The mean vertical distance was $8.85{\pm}2.59mm$, and the mean horizontal distance was $14.68{\pm}1.44mm$. The vertical (P<0.001) and the horizontal (P<0.05) distances showed significant differences between the sex groups. The success rate of the IOR-guided technique was 97.3%. Conclusion: IANB-based location of mandibular lingula showed a high success rate. From this study, we concluded that analysis of the anatomic locations for mandibular lingula and IOR-guided IANB are useful for restorative and surgical dental procedures of the mandibular molars.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.1
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• pp.117-122
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• 2010

Purpose: The purpose of this study was to measure the active force of extraocular muscles on mono- and binocular movements for 62 healthy koreans (male: 29, female: 33). Methods: The force of adduction, abduction, elevation and depression, of right and left eye on monocular movement were tested with horizontal moving distance based on corneal limbus and the force of superior oblique muscle and inferior oblique muscle on binocular movement were measured with vertical moving distance between corneal limbus. The distances were obtained by high resolution digital image processing. Results: At monocular movements of tested subjects. the power of abduction, adduction, elevation and depression of right and left eye were (male) 9.35 nun, 9.75 mm, (female) 9.02 mm, 9.52 mm, (male) 10.23 mm, 10.16 mm, (female) 10.17 mm, 10.07 mm, (male) 7.01 mm,6.91 mm, (female) 6.98 mm, 6.64 mm, (male) 7.52 mm, 6.82 mm, (female) 7.52 mm, 6.67 mm, respectively. The active force of binocular movements were 54.8% hyperergasia and 45.1% hypergasia/67.7% hyperergasia and 32.2% hypergasia with inferior oblique muscle, 64.5% hyperergasia and 35.5% hypergasia/58.1% hyperergasia and 41.9% hypergasia with superior oblique muscle, respectively. Conclusions: The force of horizontal movement was higher than vertical movement. The value of adduction was higher than abduction on horizontal movement, and the value of depression was higher than elevation on vertical movement. In the both of inferior and superior oblique muscle, the ratio of hyperergasia was higher than that of hypergasia.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.2
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• pp.143-150
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• 1984

This paper is a study on effectiveness of weight in analytical positioning of oblique photography. Oblique photographies are more economical than normal photographies as it has a larger ground coverage and as it can be applied in situations where objects of interest are difficult to be approached. But the comparatively complex methods involved, present a problem in obtaining the desired results. In view of this fact, analytical rectification was applied in normalizing the oblique photographs. As oblique photographies are extensively used in slops and mountainous regions, a number of difficulties are encountered during the control surveying. The photocoordinates of the oblique photographs, taken at $30^{\circ}$, were weighted during rectification. They were weighted as inversely proportionate to the derived formular of ${\gamma}_y=f{\cdot}tan{\frac{\theta}{2}}+y_a$, the distance of each point from the isocenter along the Y axis. By applying the weights, coordinates errors conld be reduced and the error difference between oblique and normal photographs could be reduced upto 53.2%.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.4
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• pp.429-435
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• 1998

Experiments were conducted to investigate the turbulent flow characteristics from on oblique impingement surface to an plane jet at the jet Reynolds number(Re based on the nozzle width) $3{\times}10^4$ The jet mean velocity and turbulent intensity profiles have been measured along the impingement surface by hot-wire anemometer. The nozzle-to-plate distance(H/B) ranged from 2 to 10 and the oblique angle (a) from 45 to 90 degree. Also the secondary peak of the turbulent intensity was observed at H/B=4 S/B 5 and a=90 degree. It has been found that the stagnation point shifted toward the minor flow region as the oblique angle decreased and the position of the stagnation point nearly coincided with that of the maximum turbulent intensity.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.482-494
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• 2019

In this paper, the oblique water-entry impact of a vehicle with a disk cavitator is studied experimentally and numerically. The effectiveness and accuracy of the numerical simulation are verified quantitatively by the experiments in this paper and the data available in the literature. Then, the numerical model is used to simulate the hydrodynamic characteristics and flow patterns of the vehicle under different entry conditions, and the axial force is found to be an important parameter. The influences of entry angle, entry speed and cavitator area on the axial force are studied. The variation law of the force coefficient and the dimensionless penetration distance at the peak of the axial force are revealed. The research conclusions are beneficial to engineering calculations on the impact force of a vehicle with a disk cavitator over a wide range of water-entry parameters.

• Journal of the Semiconductor & Display Technology
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• v.20 no.3
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• pp.77-82
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• 2021

This numerical study focuses on the analysis of fume particle dispersion characteristics over the surface of target workpiece in laser micro-hole machining process. The effects of oblique stagnation flow over fume generating machining point are examined by carrying out a series of three-dimensional random particle simulations along with probabilistic particle generation model and particle drag correlation of low Reynolds number. Present computational model of fume particle dispersion is found to be capable of assessing and quantifying the fume particle contamination in precision hole machining which may influenced by different types of air flow patterns and their flow intensity. The particle size dependence on dispersion distance of fume particles from laser machining point is significant and the effects of increasing flow oblique angle are shown quite differently when slot blowing or slot suction flows are applied in micro-hole machining.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.4
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• pp.257-268
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• 2003

The purpose of this study was to assess the loading distributing characteristics of implant prosthesis according to position and direction of load, under vertical and inclined loading using FEA analysis. The finite element model was designed according to standard fixture (4.1mm restorative component x 11.5mm length). The crown for mandibular first molar was made using UCLA abutment. Each three-dimensional finite element model was created with the physical properties of the implant and surrounding bone. This study simulated loads of 200N at the central fossa in a vertical direction (loading condition A), 200N at the outside point of the central fossa with resin filling into screw hole in a vertical direction (loading condition B), 200N at the centric usp in a $15^{\circ}$ inward oblique direction (loading condition C), 200N at the in a $30^{\circ}$ inward oblique direction (loading condition D) or 200N at the centric cusp in a $30^{\circ}$ outward oblique direction (loading condition E) individually. Von Mises stresses were recorded and compared in the supporting bone, fixture, and abutment screw. The following results have been made based on this study: 1. Stresses were concentrated mainly at the ridge crest around implant in both vertical and oblique loading but stresses in the cancellous bone were low in both vertical and oblique loading. 2. Bending moments resulting from non-axial loading of dental implants caused stress concentrations on cortical bone. The magnitude of the stress was greater with the oblique loading than with the vertical loading. 3. An offset of the vertical occlusal force in the buccolingual direction relative to the implant axis gave rise to increased bending of the implant. 4. The relative positions of the resultant line of force from occlusal contact and the center of rotation seems to be more important. 5. The magnitude of the stress in the supporting bone, fixture and abutment screw was greater with the outward oblique loading than with the inward oblique loading and was the greatest under loading at the centric cusp in a $30^{\circ}$ outward oblique direction. Conclusively, this study provides evidence that bending moments resulting from non-axial loading of dental implants caused stress concentrations on cortical bone. But it seems to be more important that how long is the distance from center of rotation of the implant itself to the resultant line of force from occlusal contact(leverage). The goal of improving implants should be to avoid bending of the implant.

• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.83-94
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• 2004

The purpose of this study was to compare the distributing pattern of stress according to the types of occlusal load on the finite element models of the splinted implant prostheses. The finite element model was designed with the parallel placement of two fixtures ($4.0mm{\times}11.5mm$) on mandibular first and second molars. The cemented crowns for mandibular first and second molars were made. Three-dimensional finite element model was created with the components of the implant, surrounding bone and cemented crowns. Two types of occlusal load, the point load and the surface load within 0.5 mm radius circle, were applied to the finite element models with 200N magnitude in axial(along the long axis of the implant and oblique(angulation of $30^{\circ}$ to the long axis) directions perpendicular to cuspal incline. Loads were positioned from the center of central fossa and to distance of 2 mm and 4 mm apart from the center of central fossa. Von-Mises stresses were recorded and compared in the fixtures and sections. The results were as following : 1. Under axial loading at the central fossa, the stress was distributed along the fixture except for the apical portion, not relative to both point & surface contacts. 2. With offset distance increasing, the highest stresses were concentrated in the neck portion of the fixture. 3. The maximum von Mises stress under the oblique load was greater than that under the axial load. 4. Under the oblique load, the highest stress were concentrated in the buccal side and lingual neck portion of the fixture with offset distance increasing. The results had a tendency to increase the stress on the neck portion of fixture with the offset and oblique loads increasing. The design of occlusal scheme should be allowed to distribute stress axially in maximum intercuspation and to decrease the angulation of cuspal incline.