• Journal of Biosystems Engineering
• /
• v.40 no.1
• /
• pp.28-34
• /
• 2015

Purpose: This study aimed to install an RTK-GPS (Real Time Kinematic-Global Positioning System) and IMU (Inertial Measurement Unit) on a tractor used in a farm to measure positions, pasture topography, posture angles, and vibration accelerations, translate the information into maps using the GIS, analyze the characteristics of grass harvesting work, and establish new technologies and construction standards for pasture infrastructure improvement based on the analyzed data. Method: Tractor's roll, pitch, and yaw angles and vibration accelerations along the three axes during grass harvesting were measured and a GIS map prepared from the data. A VRS/RTK-GPS (MS750, Trimble, USA) tractor position measuring system and an IMU (JCS-7401A, JAE, JAPAN) tractor vibration acceleration measuring systems were mounted on top of a tractor and below the operator's seat to obtain acceleration in the direction of progression, transverse acceleration, and vertical acceleration at 10Hz. In addition, information on regions with bad workability was obtained from an operator performing grass harvesting and compared with information on changes in tractor posture angles and vibration acceleration. Results: Roll and pitch angles based on the y-axis, the direction of forward movements of tractor coordinate systems, changed by at least $9-13^{\circ}$ and $8-11^{\circ}$ respectively, leading to changes in working postures in the central and northern parts of the pasture that were designated as regions with bad workability during grass harvesting. These changes were larger than those in other regions. The synthesized vectors of the vibration accelerations along the y-axis, the x-axis (transverse direction), and the z-axis (vertical direction) were higher in the central and northwestern parts of the pasture at 3.0-4.5 m/s2 compared with other regions. Conclusions: The GIS map developed using information on posture angles and vibration accelerations by position in the pasture is considered sufficiently utilizable as data for selection of construction locations for pasture infrastructure improvement.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.67 no.8
• /
• pp.1080-1088
• /
• 2018

General methods of controlling a drone are divided into manual control and automatic control, which means a drone moves along the route. In case of manual control, a man should be able to figure out the location and status of a drone and have a controller to control it remotely. When people control a drone, they collect information about the location and position of a drone with the eyes and have its internal information such as the battery voltage and atmospheric pressure delivered through telemetry. They make a decision about the movement of a drone based on the gathered information and control it with a radio device. The automatic control method of a drone finding its route itself is not much different from manual control by man. The information about the position of a drone is collected with the gyro and accelerator sensor, and the internal information is delivered to the CPU digitally. The location information of a drone is collected with GPS, atmospheric pressure sensors, camera sensors, and ultrasound sensors. This paper presents an investigation into drone control by a remote computer. Instead of using the automatic control function of a drone, this approach involves a computer observing a drone, determining its movement based on the observation results, and controlling it with a radio device. The computer with a Depth camera collects information, makes a decision, and controls a drone in a similar way to human beings, which makes it applicable to various fields. Its usability is enhanced further since it can control common commercial drones instead of specially manufactured drones for swarm flight. It can also be used to prevent drones clashing each other, control access to a drone, and control drones with no permit.

• Korean Journal of Applied Biomechanics
• /
• v.15 no.4
• /
• pp.169-179
• /
• 2005

In the 500m short track speed skating, the matter of who reaches the first corner first can important factor since each competitor races with all speed from the start to the first line. A filed study was attempted to kinematical estimation six female foreign skaters, who participated in the 500m female final round competition, and two Korea skates during the World Short track Skating Championship. The three dimensional motion analysis with DLT method was executed using four video cameras for analyzing the actual competition situation. In point of analyzing the actual competition situation, it is expected that skaters and coaches the effective informations, and the following conclusions are drawn; The elapsed time by phase in start motion of the foreign skaters appeared shorter those of Korea skaters, so the start training of Korea skaters should be strengthed. Also the displacement of C.G in the foreign skaters appeared shorter displacement than those of Korea skaters. Especially in the starting position, the foreign skaters are superior to Korea skaters in displacement of first(left) and next following stroke(right). The velocity of C.G and maximum velocity of skate blade of foreign skaters art faster than those of Korea skaters. And the foreign skaters show the superior early velocity change. Both of leaning body angle, and left and knee angle of the foreign skaters lead to positive point of having the propulsive force in the early starting position. Observing in the most prominent feature of foreign and Korea skaters in start phase, foreign skaters skate quickly the third stroke. These features of Korea skaters would appear disadvantage of location selection in entering the coner course.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.11
• /
• pp.1750-1759
• /
• 2020

The characterization of cytochrome P450 CYP125A13 from Streptomyces peucetius was conducted using cholesterol as the sole substrate. The in vitro enzymatic assay utilizing putidaredoxin and putidaredoxin reductase from Pseudomonas putida revealed that CYP125A13 bound cholesterol and hydroxylated it. The calculated K_D value, catalytic conversion rates, and Km value were 56.92 ± 11.28 μM, 1.95 nmol min^-1 nmol^-1, and 11.3 ± 2.8 μM, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis showed that carbon 27 of the cholesterol side-chain was hydroxylated, characterizing CYP125A13 as steroid C27-hydroxylase. The homology modeling and docking results also revealed the binding of cholesterol to the active site, facilitated by the hydrophobic amino acids and position of the C27-methyl group near heme. This orientation was favorable for the hydroxylation of the C27-methyl group, supporting the in vitro analysis. This was the first reported case of the hydroxylation of cholesterol at the C-27 position by Streptomyces P450. This study also established the catalytic function of CYP125A13 and provides a solid basis for further studies related to the catabolic potential of Streptomyces species.

• Journal of Fashion Business
• /
• v.21 no.6
• /
• pp.66-76
• /
• 2017

This study used a virtual wearing system equipped with body shape data with a 3D scanner, based on a female basic bodice, to develop a modified Hanbok Jeogori with high fitness capabilities to provide basic data for the development of the modified Hanbok Jeogori pattern for the academic and industrial fields. In this study, the representative modified Hanbok design which most frequently appeared in broadcasting ads and on line was selected. The wearing test was conducted by six professionals, and three times wearing tests were implemented based on 17 evaluation items. The data for this study was processed statistically using SAS 9.0. We conducted, the F-test for significance verification, the Duncan-test for a post test, and a correlation analysis of Cronbach's alpha coefficient for a reliability test of dressing test results were implemented for each of the three tests. The pattern of the developed modified Hanbok Jeogori overcame the defects of the short length of the conventional modified hanbok, and could fix the length issue. The developed Hanbok pattern solved the overlapping problem of the shoulder, back neck point-sleeve length(Whajang), and armhole, displayed in a straight line from the Godae point of the previous modified Hanbok; it suggested the position of the Seop and neck line in the basic bodice. Based on this, the Seop width, Git form, Goreum and the width, length, and position of the string whose dimensions can differ in accordance with the trend can be applied in various forms.

• Korean Journal of Metals and Materials
• /
• v.49 no.12
• /
• pp.983-988
• /
• 2011

Failure analyses of the screws in spinal fixation devices were carried out. The fractured screws were retrieved from a patient who had spinal surgery in the thoracic vertebrae from number 10 to 15. The failure occurred one month after the removal of the braces. Microstructures and fracture surfaces were examined by optical and scanning electron microscopy. The microstructures of the screws corresponded to annealed Ti-6Al-4V bar. However, in the vicinity of the screw surface, there was an insufficient number of fine precipitates. Fracture surfaces showed typical fatigue failure modes. Regarding the fact that no machining defects were detected, fatigue crack initiation might have been caused by the lack of precipitates near the screw surfaces. Only the fourth of five fixed screws was severely stress-concentrated by the action of the spinal bones, while the stress of the 4th screw was decreased to half of its acceptable level when the screw was supplemented by one more, which might have been fixed in the 6th vertebra under the 5th position by the switching of its position. The stress simulation was conducted by ANSYS with 3D CAD of PRO/E in order to understand the stress concentration behavior and to provide an effective spinal surgery guide.

• Nuclear Engineering and Technology
• /
• v.51 no.5
• /
• pp.1417-1427
• /
• 2019

In this study, we evaluated the performance of a commercial pixelated cadmium zinc telluride (CZT) detector for spectroscopy and identified its feasibility as a Compton camera for radiation monitoring in a nuclear power plant. The detection system consisted of a $20mm{\times}20mm{\times}5mm$ CZT crystal with $8{\times}8$ pixelated anodes and a common cathode, in addition to an application specific integrated circuit. The performance of the various radioisotopes $^{57}Co$, $^{133}Ba$, $^{22}Na$, and $^{137}Cs$ was evaluated. In general, the amplitude of the induced signal in a CZT crystal depends on the interaction position and material non-uniformity. To minimize this dependency, a drift time correction was applied. The depth of each interaction was calculated by the drift time and the positional dependency of the signal amplitude was corrected based on the depth information. After the correction, the Compton regions of each spectrum were reduced, and energy resolutions of 122 keV, 356 keV, 511 keV, and 662 keV peaks were improved from 13.59%, 9.56%, 6.08%, and 5%-4.61%, 2.94%, 2.08%, and 2.2%, respectively. For the Compton imaging, simulations and experiments using one $^{137}Cs$ source with various angular positions and two $^{137}Cs$ sources were performed. Individual and multiple sources of $^{133}Ba$, $^{22}Na$, and $^{137}Cs$ were also measured. The images were successfully reconstructed by weighted list-mode maximum likelihood expectation maximization method. The angular resolutions and intrinsic efficiency of the $^{137}Cs$ experiments were approximately $7^{\circ}-9^{\circ}$ and $5{\times}10^{-4}-7{\times}10^{-4}$, respectively. The distortions of the source distribution were proportional to the offset angle.

• Archives of Orthopedic and Sports Physical Therapy
• /
• v.14 no.2
• /
• pp.1-8
• /
• 2018

Purpose: This study investigated the effect of the augmented reality (AR)-based knee joint short period exercise program and used a motion analyzer with a 3D camera to determine the range of motion and dynamic balance and further investigate the effects of therapeutic exercise on patients. Methods: This study used AR-based motion analysis and a Y-balance test to measure the range of motion (ROM) of each joint: the hip joint and the knee joint. After the measurements, an exercise program was applied to the subjects, using the knee motion program function, and the muscles of the quadriceps femoris and the hamstring were stretched or strengthened. Results: Our results showed knee joint extension at the dominant hip joint flexion position. While there was no significant difference (p>.05) at this position, there were significant differences in the non-dominant hips, unbalanced knee joint flexion, and superior knee joint flexion (p<.05). The Y-balance test using the non-dominant leg supported by the dominant legs showed that the absolute reach was $69.70{\pm}7.06cm$ before the exercise, and the absolute reach after the exercise was $77.56{\pm}6.09cm$ (p<.05). Conclusions: There was a significant difference when the movement of the lower limbs supported the superior limbs, and a significant difference was found in the ROM when the non-dominant side supported the dominant side. Therefore, the AR-based exercise program improves the balance of the human body and the range of motion of the joints, and research that aims to improve patients abilities should continue.

• The korean journal of orthodontics
• /
• v.54 no.4
• /
• pp.247-256
• /
• 2024

Objective: This retrospective study evaluated the mandibular condyle position before and after bimaxillary orthognathic surgery performed with the mandibular condyle positioned manually in patients with mandibular prognathism using cone-beam computed tomography. Methods: Overall, 88 mandibular condyles from 44 adult patients (20 female and 24 male) diagnosed with mandibular prognathism due to skeletal Class III malocclusion who underwent bilateral sagittal split ramus osteotomy (BSSRO) and Le Fort I performed using the manual condyle positioning method were included. Cone-beam computed tomography images obtained 1-2 weeks before (T0) and approximately 6 months after (T1) surgery were analyzed in three planes using 3D Slicer software. Statistical significance was set at P < 0.05 level. Results: Significant inward rotation of the left mandibular condyle and significant outward rotation of the right mandibular condyle were observed in the axial and coronal planes (P < 0.05). The positions of the right and left condyles in the sagittal plane and the distance between the most medial points of the condyles in the coronal plane did not differ significantly (P > 0.05). Conclusions: While the change in the sagittal plane can be maintained as before surgery with manual positioning during the BSSRO procedure, significant inward and outward rotation was observed in the axial and coronal planes, respectively, even in the absence of concomitant temporomandibular joint disorder before or after the operation. Further long-term studies are needed to correlate these findings with possible clinical consequences.

• The Journal of Korean Society for Radiation Therapy
• /
• v.26 no.2
• /
• pp.239-245
• /
• 2014

Purpose : The purpose of this study is to verify the accuracy of dose delivery according to the pitch and roll rotational setup error with 6D robotic couch in Intensity Modulated Radiation Therapy (IMRT) for pelvic region in patients. Materials and Methods : Trilogy(Varian, USA) and 6D robotic couch(ProturaTM 1.4, CIVCO, USA) were used to measure and analyze the rotational setup error of 14 patients (157 setup cases) for pelvic region. The total 157 Images(CBCT 78, Radiography 79) were used to calculate the mean value and the incidence of pitch and roll rotational setup error with Microsoft Office Excel 2007. The measured data (3 mm, 3%) at the reference angle ($0^{\circ}$) without couch rotation of pitch and roll direction was compared to the others at different pitch and roll angles ($1^{\circ}$, $1.5^{\circ}$, $2^{\circ}$, $2.5^{\circ}$) to verify the accuracy of dose delivery by using 2D array ionization chamber (I'mRT Matrixx, IBA Dosimetry, Germany) and MultiCube Phantom(IBA Dosimetry, Germany). Result from the data, gamma index was evaluated. Results : The mean values of pitch and roll rotational setup error were $0.9^{\circ}{\pm}0.7$, $0.5^{\circ}{\pm}0.6$. The maximum values of them were $2.8^{\circ}$, $2.0^{\circ}$. All of the minimum values were zero. The mean values of gamma pass rate at four different pitch angles ($1^{\circ}$, $1.5^{\circ}$, $2^{\circ}$, $2.5^{\circ}$) were 97.75%, 96.65%, 94.38% and 90.91%. The mean values of gamma pass rate at four different roll angles ($1^{\circ}$, $1.5^{\circ}$, $2^{\circ}$, $2.5^{\circ}$) were 93.68%, 93.05%, 87.77% and 84.96%. when the same angles ($1^{\circ}$, $1.5^{\circ}$, $2^{\circ}$) of pitch and roll were applied simultaneously, The mean values of each angle were 94.90%, 92.37% and 87.88%, respectively. Conclusion : As a result of this study, it was able to recognize that the accuracy of dose delivered is lowered gradually as pitch and roll increases. In order to increase the accuracy of delivered dose, therefore, it is recommended to perform IGRT or correct patient's position in the pitch and roll direction, to improve the quality of treatment.