• Journal of Biosystems Engineering
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• v.4 no.1
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• pp.1-23
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• 1979

The use of barley seeder attached to rotary tiller in the rural area has a significant meaning not only for the solution of labor peak season, but also for the increase of land utilization efficiency. The facts that presently being used barley seeders are all based on the mechanical principles of the reverse rotation, center drive and are all using forward rotating tine, which is used to be easily and heavily worn out when it rotates reversely, raise problem of recommending them to rural area in Korea. Therefore, the main objective of the study was to develop new type of rotary tine attachable to barley seeders. To attain the objective the following approaches were applied. (1) The kinematic analysis of reverse rotating barley seeders. (2) The studies on the soil bin and artificial soil. (3) The comparative experiment on the power requirement of prototype tine. The results obtained from the studies are summarized as follow: 1. The kinematic analysis of barley seeder attached to rotary tiller: The following results were obtained from the kinematic analysis for deriving general formulae of the motion and velocity characterizing the rotary tine of barley seeders presently being used by farmers. a) The position vector (P) of edge point (P) in the rotary tine of reverse rotating, center drive was obtained by the following formula. $$P=(vt+Rcos wt)i+Rsin wt j+ \{ Rcos \theta r sin \alpha cos (wt- \beta +\theta r) +Rsin \theta r sin \alpha sin (wt-\beta + \theta r) \} lk $$ b) The velocity of edge point $(P^')$ of reverse rotating, center drive rotary tine was obtained by the following formula. $$(P^')=(V-wR sin wt)i+(w\cdot Rcoswt)j + \{ -w\cdot Rcos \theta r\cdot sin \alpha \cdot sin (wt-\beta +\theta r) + w\cdot Rsin \theta r\cdot sin \alpha \cdot cos (wt- \beta + \theta r \} k $$ c) In order to reduce the power requirement of rotary tine, the angle between holder and edge point was desired to be reduced. d) In order to reduce the power requirement, the edge point of rotary tine should be moved from the angle at the begining of cutting to center line of machine, and the additional cutting width should be also reduced. 2. The studies on the soil bin and artificial soil: In order to measure the power requirement of various cutting tines under the same physical condition of soil, the indoor experiments Viere conducted by filling soil bin with artificially made soil similar to the common paddy soil and the results were as follows: a) When the rolling frequencies$(x)$ of the artificial soil were increased, the densIty$(Y)$ was also increased as follows: $$y=1.073200 +0.070780x - 0.002263x^2 (g/cm^3)$$ b) The absolute hardness $(Y)$ of soil had following relationship with the rolling frequencies$(x)$ and were increased as the rolling frequencies were increased. $$Y=37.74 - \frac {0.64 + 0.17x-0. 0054x^2} {(3.36-0.17x + 0.0054x^2)^3} (kg/cm^3)$$ c) The density of soil had significant effect on the cohesion and angle of internal friction of soil. For instance, the soil with density of 1.6 to 1.75 had equivalent density of sandy loam soil with 29.5% of natural soil moisture content. d) The coefficient of kinetiic friction of iron plate on artificial soil was 0.31 to 0.41 and was comparable with that of the natural soil. e) When the pulling speed of soil bin was the 2nd forward speed of power tiller, the rpm of driving shaft of rotary was similar to that of power tiller, soil bin apparatus is indicating the good indoor tester. 3. The comparative experiment on the power requirement of prototype tine of reverse rotating rotary: According to the preliminary test of rotary tine developed with various degrees of angle between holder and edge pcint due to the kinematic analysis, comparative test between prototype rotary tine with $30 ^\circ $ and $10 ^\circ$ of it and presently being used rotary tine was carried out 2nd the results were as follows: a) The total cutting torque was low when the angle between holder and edge point was reduced. b) $\theta r$ (angle between holder and edge point) of rotary tine seemed to be one: of the factors maximizing the increase of torque. c) As the angle between holder and edge point ($\theta r$) of rotary tine was $30 ^\circ $ rather than $45 ^\circ $, the angle of rotation during cutting soil was reduced and the total cutting torque was accordingly reduced about 10%, and the reduction efficiency of total cutting torque was low when the angle between holder and edge point ($\theta r$) of rotary tine was $10 ^\circ $, which indicates that the proper angle between holder and edge point of rotary tine should be larger than $10 ^\circ $ and smaller than $30 ^\circ $ . From above results, it could be concluded that the use of the prototype rotary tine which reduced the angle between holder and edge point to $30 ^\circ $, insted of $45 ^\circ $, is disirable not only decreasing the power requirements, but also increasing the durabie hour of it. Also forward researches are needed, WIlich determine the optimum tilted angle of rotary brocket, and rearrangement of the rotary tine on the rotary boss.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1972.03a
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• pp.2.3-2
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• 1972

The vestibular function test reveals the objective findings of the impairment of the vestibular labyrinth. It's purpose is based on the analysis of the findings and detect the location and etiology of the labyrinthine impairment. In the vestibular function test, the vestibulo-spinal reflex has the clinical significance upon the tonus of the striated muscles by the labyrithine stimulation and contribute to regulating the posture and the position, at rest as well as in motion. The vestibulo-spinal reflex must performe as one of the routine vestivular function test because it can be evoked in man by such weak stimuli to the labyrinth as cannot induce vestibulo-ocular reflex. Authors performed the vestibular function test such as one leg test, gait test, stepping test and vertical writing test to one hundred of healthy and young male adult and received the following results. Results 1. One leg test: In 30 seconds, the frequency of dropping the leg on the ground was between 0 to 3 times in Rt., and 0 to 5 times in Lt. The mean frequency was 0.48 times in Rt., and 0.68 times in Lt. 2. Gait test: In forward gait; the range of the deviation was distributed 0 to 100 cm and mean range was 22.5cm to the Rt., 26.1cm to the Lt. In backward gait; the range deviation was distributed 0 to 140cm and mean range was 35.4cm to the Rt., 33.0cm to the Lt. 3. Stepping test: In normal head position; forward movement war 93% and backward 5%. The angle of displacement deviated to the Rt. side in 36%, and Lt. in 50%. The angle of rotation deviated to the Rt. side in 53 %, and Lt. in 36%. The mean values: angle of displacement was 22.05 degrees, angle of rotation was 24.40 degrees, distance of displacement was 48.95cm. In backward head position; Forward movement was 94% and backward was 3%. The angle of displacement deviated in 34%, and Rt. in 55%, to the Rt. side The angle of rotation deviated to the Rt. side in 50%, and Lt. in 42%. The mean values; angle of displacement was 29.72 degrees, angle of rotation was 39.53 degrees, distance of displacement was 44.17cm. 44.17cm. 4. Vertical writing test: The angle of deviation was between 0 to 16 degrees in all cases, and was between 0 to 12 degrees in the cases of normal head position. The mean angle of deviation was between 4.15 to 5.76 degrees on each side. The direction of deviation to the Rt. side was 54~69%, Lt. was 25~40% and 3~7% was vertical without deviation.

• Journal of Korean Orthopaedic Sports Medicine
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• v.1 no.2
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• pp.154-158
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• 2002

Purpose: To compare the results of open and arthroscopic method in recurrent anterior should erinstability. Materials and Methods: The 68 patients who have been taken the open or arthroscopic Bankartrepair for the period of Jan. 1995 to April. 2000. One group (23 patients) had elected an arthroscopic Bankart repair, the other group (45 patients) had chosen open stabilization. Patients were followed up12 to 63 months (ave. 34 months) after surgery. Results: We found 2 cases of subluxation out of open repair group, and then treated by conservative method. There were another 2 cases of dislocation and 2 cases of subluxation out of arthroscopicrepair group, and we have taken out 1 case of reoperation by open method. Using the functional scales by Rowe, the patients who have taken the open method posted at the average point of 87, while the arthroscopic method posted 85 points. Patients satisfaction points were 84.6 and 72.5 respectively. There were no criteria of statistically significant except stability and motion score. Conclusion: Open Bankart repair would be better in stability, and arthroscopic method in ROM gain. Proper patient selection based on physical examination and arthroscopic inspection to optimize the indications contributed to successful treatment.

• Cartoon and Animation Studies
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• s.26
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• pp.1-30
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• 2012

The purpose of animation is to give interesting stories to an audience through motion. To achieve the purpose, over the past century since its inception, animation has adopted many kinds of technologies, and thus developed diverse narrative methods and visual expression techniques. In addition, with the advancement of expression techniques, all elements making up animation have gradually been systemized, and at the same time, have helped express the worlds beyond the reality. As a result, people have faced the era when an audience can watch everything imaginated by an animation director on a big screen. These days, more efforts have been made in order for the audience to feel much more than enjoy pictures moving in a frame. In other words, the purpose of the animation is changing from the passive viewing of animation to feeling and sensing stuffs through the animation. In the center of the changing process is 3D technology which gives new interesting to an audience. Sometime ago, a 3D animation movie was produced in Korea. But it did not bring out box-office profits, for it failed to give satisfaction to an audience who expected high perfection and beauty being able to be rivalled to those of international 3D animation movies. The failure is attributable to the fact that the domestic 3D animation production industry is merely in the early stage, and has not sufficient human resources, technology, and experiences in producing 3D animation films. Moreover, the problem is that most studies on 3D focus on the technologies related to reenactment, but that few studies on the images, which an audience directly faces, have been conducted. Under the domestic circumstance, the study on stereoscopic image screen of , a 3D stereoscopic animation film which was released in 2010 and has been seen as the best successful 3D stereoscopic animation, is worthwhile. Thus this thesis conducted theoretical consideration and case analysis focusing on the visual direction that creates the pictures to deliver abundant three dimensional effect so that it can be used as a basic data when producing high quality-domestic 3D animation and training professional labor forces. In the result, it was found that the 3D animation was not a new area, but the area which has been expanded and changed by applying the characteristics of 3D image based on the principles of the existing media aesthetics. This study might be helpful to establish the foundation of the theoretical studies necessary for producing 3D animation contents for realizing the sense of reality.

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.169-193
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• 2016

In order to characterize the Neotectonic crustal deformation and current stress field in and around the Korean Peninsula and to interpret their tectonic implications, this paper synthetically analyzes the previous Quaternary fault and focal mechanism solution data and recent geotechnical in-situ stress data and examines the characteristics of crustal deformations and tectonic settings in and around East Asia after the Miocene. Most of the Quaternary fault outcrops in SE Korea occur along major inherited fault zones and show a NS-striking top-to-the-west thrust geometry, indicating that the faults were produced by local reactivation of appropriately oriented preexisting weaknesses under EW-trending pure compressional stress field. The focal mechanism solutions in and around the Korean Peninsula disclose that strike-slip faulting containing some reverse-slip component and reverse-slip faulting are significantly dominant on land and in sea area, respectively. The P-axes are horizontally clustered in ENE-WSW direction, whereas the T-axes are girdle-distributed in NNW direction. The geotechnical in-situ stress data in South Korea also indicate the ENE-trending maximum horizontal stress. The current crustal deformation in the Korean Peninsula is thus characterized by crustal contraction under regional ENE-WSW or E-W compression stress field. Based on the regional stress trajectories in and around East Asia, the current stress regime is interpreted to have resulted from the cooperation of westward shallow subduction of the Pacific Plate and collision of Indian and Eurasian continents, whereas the Philippine Sea plate have not a decisive effect on the stress-regime in the Korean Peninsula due to its high-angle subduction that resulted in dominant crust extension of the back-arc region. It is also interpreted that the Neotectonic crustal deformation and present-day tectonic setting of East Asia commenced with the change of the Pacific Plate motion during 5~3.2 Ma.

• Journal of the Korean Applied Science and Technology
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• v.38 no.4
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• pp.951-962
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• 2021

The purpose of this study was to analyze the effects of smart machine circulation exercise on body composition, lung function, blood lipid and insulin resistance in obesity middle-aged women among 40-60 years by dividing them into a smart machine circulation exercise group(n=8), and control group(n=6). The smart machine circulation exercise program included 55-minutes sessions thrice each week at the following intensities: The strength of aerobic exercise is applied to smart machines by linking the smart machine with the POLAR T31; the 1-4 week is 40-50%HRR, 5-8 week is 50-60%HRR, and 9-10 week is 60-70%HRR. The strength of the resistance exercise was tested using a smart machine based on the constant velocity motion, and then, using the 1-RM data value, applied 40% 1-RM for 1-4 weeks, 60% 1-RM for 5-8 weeks, and 80% 1-RM for 9-10 week. As a results, body composition indicated that weight, BMI, %BF, WHR had a significant interaction effect. Lung function indicated that FVC levels significantly changes in the exercise group and the between groups difference in changes at 10week was significant. Also, FVC and FEV₁ significantly showed interaction effect. TC, TG and HDL-C levels significantly changes in smart machine circulation exercise group and the between-group difference in changes after 10 weeks was significant. TC, TG and HDL-C significantly showed interaction effect. Insulin resistance demonstrated that Insulin, Glucose and HOMA-IR levels significantly showed difference over 10 weeks between group. Therefore, the 10 weeks smart machine circulation exercise positively effects on the body composition, lung function, blood lipids, and insulin resistance in obesity middle-aged women and this smart machine circulation exercise can improve their obesity and prevent obesity.

• Journal of Navigation and Port Research
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• v.42 no.6
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• pp.427-436
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• 2018

In this study, experimental and numerical analysis were performed on the survivability of a long pipe-type buoy structure in waves. The buoy structure is an articulated tower consisting of an upper structure, buoyancy module, and gravity anchor with long pipes forming the base frame. A series of experiment were performed in the ocean engineering basin of KRISO with the scaled model of 1/ 22 to evaluate the survivability of the buoy structure at West Sea in South Korea. Survival condition was considered as the wave of 50 year return period. Additional experiments were performed to investigate the effects of current and wave period. The factors considered for the evaluation of the buoy's survival were the pitch angle of the structure, anchor reaction force, and the number of submergence of the upper structure. Numerical simulations were carried out with the OrcaFlex, the commercial program for the mooring analysis, with the aim of performing mutual validation with the experimental results. Based on the evaluation, the behavior characteristics of the buoy structure were first examined according to the tidal conditions. The changes were investigated for the pitch angle and anchor reaction force at HAT and LAT conditions, and the results directly compared with those obtained from numerical simulation. Secondly, the response characteristics of the buoy structure were studied depending on the wave period and the presence of current velocity. Third, the number of submergence through video analysis was compared with the simulation results in relation to the submergence of the upper structure. Finally, the simulation results for structural responses which were not directly measured in the experiment were presented, and the structural safety discussed in the survival waves. Through a series of survivability evaluation studies, the behavior characteristics of the buoy structure were examined in survival waves. The vulnerability and utility of the buoy structure were investigated through the sensitivity studies of waves, current, and tides.

• Journal of Korea Water Resources Association
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• v.52 no.10
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• pp.743-752
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• 2019

The flow in the meandering channel is characterized by the spiral motion of secondary currents that typically cause the erosion along the outer bank. Hydraulic structures, such as spur dike and groyne, are commonly installed on the channel bottom near the outer bank to mitigate the strength of secondary currents. This study is to investigate the effects of submerged vanes installed in a $90^{\circ}$ meandering channel on the development of secondary currents through three-dimensional numerical modeling using the hybrid RANS/LES method for turbulence and the volume of fluid method, based on OpenFOAM open source toolbox, for capturing the free surface at the Froude number of 0.43. We employ the second-order-accurate finite volume methods in the space and time for the numerical modeling and compare numerical results with experimental measurements for evaluating the numerical predictions. Numerical results show that the present simulations well reproduce the experimental measurements, in terms of the time-averaged streamwise velocity and secondary velocity vector fields in the bend with submerged vanes. The computed flow fields reveal that the streamwise velocity near the bed along the outer bank at the end section of bend dramatically decrease by one third of mean velocity after the installation of vanes, which support that submerged vanes mitigate the strength of primary secondary flow and are helpful for the channel stability along the outer bank. The flow between the top of vanes and the free surface accelerates and the maximum velocity of free surface flow near the flow impingement along the outer bank increases about 20% due to the installation of submerged vanes. Numerical solutions show the formations of the horseshoe vortices at the front of vanes and the lee wakes behind the vanes, which are responsible for strong local scour around vanes. Additional study on the shapes and arrangement of vanes is required for mitigate the local scour.

• Journal of the Society of Disaster Information
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• v.16 no.4
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• pp.813-823
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• 2020

Purpose: In order to maximize the stability and productivity of the work through simulation prior to high-risk facilities and high-cost work such as dismantling the facilities inside the reactor, we intend to use digital twin technology that can be closely controlled by simulating the specifications of the actual control equipment. Motion control errors, which can be caused by the time gap between precision control equipment and simulation in applying digital twin technology, can cause hazards such as collisions between hazardous facilities and control equipment. In order to eliminate and control these situations, prior research is needed. Method: Unity 3D is currently the most popular engine used to develop simulations. However, there are control errors that can be caused by time correction within Unity 3D engines. The error is expected in many environments and may vary depending on the development environment, such as system specifications. To demonstrate this, we develop crash simulations using Unity 3D engines, which conduct collision experiments under various conditions, organize and analyze the resulting results, and derive tolerances for precision control equipment based on them. Result: In experiments with collision experiment simulation, the time correction in 1/1000 seconds of an engine internal function call results in a unit-hour distance error in the movement control of the collision objects and the distance error is proportional to the velocity of the collision. Conclusion: Remote decomposition simulators using digital twin technology are considered to require limitations of the speed of movement according to the required precision of the precision control devices in the hardware and software environment and manual control. In addition, the size of modeling data such as system development environment, hardware specifications and simulations imitated control equipment and facilities must also be taken into account, available and acceptable errors of operational control equipment and the speed required of work.

• Trans-
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• v.15
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• pp.25-56
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• 2023

VR is a dynamic image simulation technology with very high information density. Among them, spatial depth, temporality, and realism bring an unprecedented sense of immersion to the experience. However, due to its high information density, the information contained in it is very easy to be manipulated, creating an illusion of objectivity. Users need guidance to help them interpret the high density of dynamic image information. Just like setting up navigation interfaces and interactivity in games, interactivity in virtual reality is a way to interpret virtual content. At present, domestic research on VR content is mainly focused on technology exploration and visual aesthetic experience. However, there is still a lack of research on interactive storytelling design, which is an important part of VR content creation. In order to explore a better interactive storytelling model in virtual reality content, this paper analyzes the interactive storytelling features of the VR animated version of <Wolves in the walls> through the methods of literature review and case study. We find that the following rules can be followed when creating VR content: 1. the VR environment should fully utilize the advantages of free movement for users, and users should not be viewed as mere observers. The user's sense of presence should be fully considered when designing interaction modules. Break down the "fourth wall" to encourage audience interaction in the virtual reality environment, and make the hot media of VR "cool". 2.Provide developer-driven narrative in the early stages of the work so that users are not confused about the ambiguous world situation when they first enter a virtual environment with a high degree of freedom. 1.Unlike some games that guide users through text, you can guide them through a more natural interactive approach that adds natural dialog between the user and story characters (NPC). Also, since gaze guidance is an important part of story progression, you should set up spatial scene user gaze guidance elements within it. For example, you can provide eye-following cues, motion cues, language cues, and more. By analyzing the interactive storytelling features and innovations of the VR animation <Wolves in the walls>, I hope to summarize the main elements of interactive storytelling from its content. Based on this, I hope to explore how to better showcase interactive storytelling in virtual reality content and provide thoughts on future VR content creation.