• Wind and Structures
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• v.37 no.1
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• pp.57-78
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• 2023

In this study, a generalized three-degree-of-freedom (3-DoF) analytical model is formulated to predict linear aerodynamic instabilities of a prism under quasi-steady (QS) conditions. The prism is assumed to possess a generic cross-section exposed to turbulent wind flow. The 3-DoFs encompass two orthogonal horizontal directions and rotation about the prism body axis. Inertial coupling is considered to account for the non-coincidence of the mass center and the rotation center. The aerodynamic force coefficients-drag, lift, and moment-depend on the Reynolds number based on relative flow velocity, angle of attack, and the angle between the wind and the cable. Aerodynamic forces are linearized with respect to the static equilibrium configuration and mean wind velocity. Routh-Hurwitz and Liénard and Chipart criteria are used in the eigenvalue problem, yielding an analytical solution for instabilities in galloping and static divergence types. Additionally, the minimum structural damping and stiffness required to prevent these instabilities are numerically determined. The proposed 3-DoF instability model is subsequently applied to a conductor with ice accretion and a full-scale dry inclined cable. In comparison to existing models, the developed model demonstrates superior prediction accuracy for unstable regions compared with results in wind tunnel tests.

• Steel and Composite Structures
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• v.44 no.6
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• pp.789-801
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• 2022

In order to study the influence of loading angles on seismic performance of steel reinforced concrete (SRC) special-shaped columns, cyclic loading tests and finite element analysis (FEA) were both carried out. Seven SRC special-shaped columns, including two L-shaped columns, three T-shaped columns and two cross-shaped columns, were tested, and the failure patterns of the columns with different loading angles were obtained. Based on the tests, the FEA models of SRC special-shaped columns with different loading angles were established. According to the simulation results, hysteretic curves and seismic performance indexes, including bearing capacity, ductility, stiffness and energy dissipation capacity, were analyzed in detail. The results showed that the failure patterns were different for the columns with the same section and different loading angles. With the increasing of loading angles, the hysteretic curves became fuller and the bearing capacity and initial stiffness appeared increasing tendency, but the energy dissipation capacity changed insignificantly. When the loading angle changed, the ductility got better with the larger area of steel at the failure side for the unsymmetrical section and near the neutral axis for the symmetrical section, respectively.

• The korean journal of orthodontics
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• v.30 no.1 s.78
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• pp.53-66
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• 2000

This study was performed to find out the effect of projection errors on cephalometric linear and angular measurements according to head rotation during taking lateral cephalometric radiographs. Seventeen skulls with permanent dentition and no gross asymmetry were obtained from the Department of Anatomy, Medical School, Chosun University. Total 527 x-ray films were taken with $1^{\circ}$ interval from the reference position($0^{\circ}$) to ${\pm}15^{\circ}$ around the vertical axis (Z axis) which is perpendicular to the midpoint of the line connecting the center of two ear rods in submento-vertex direction. Statistical analysis was performed by paired t-test if there were statistically significant differences between the mean of the reference position($0^{\circ}$) and that of each rotation angle. The following results were obtained. 1. The projection errors of angular measurements were smaller than those of linear measurements. 2. The projection errors of angular measurements including midline landmarks were smaller than those including bilateral landmarks. 3. The horizontal linear measurements were gradually decreased when the stroll was rotated toward the film, but slightly increased and then decreased when the skull was rotated toward the focal spot. However, the changes were smaller in focal direction. 4. The projection errors of horizontal linear measurements were larger than those of vertical linear measurements. 5. The projection errors of vertical linear measurements were increased with increased distance from the rotation axis to vertical measurements. It is concluded that the use of angular measurements rather than linear measurements is recommended to minimize the projection errors.

• Cartoon and Animation Studies
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• s.41
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• pp.75-106
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• 2015

Animations characterize space as a strategy to effectively show the inner conflicts of characters and to highlight the theme. During the process of inner conflict, characters unconsciously use defense mechanism to protect their egos from the fear that came from deficiency, and because of the self-deceptive quality of self-defense mechanism, the reality is distorted and conflicts get intensified. This study focuses on the concept of anti-house, the space where conflicts get intensified, analyzes animations to find out the aspect of inner conflict, and interprets the characteristic of space that is used for metaphoric structure frame. Also, it aims to reveal how the defense mechanism, which intensifies the inner conflict of characters, is characterized as anti-house. The analysis in this study was mainly done with the TV series, , and the theater version of . It is because the characters have serious deficiency from broken home and have a psychological quality of closed boundary that is symbolized as 'A.T. field'. Especially, the core character, 'Shinji Ikari', shows how a character uses compulsive self-defense mechanism to deal with inner conflict and as a result, goes through ego-collapse and then introspection. This process of the character's experience is the core of the whole plot. Through analysis, the relationship between the character's self-defense mechanism and the space, anti-house(which expands to Anti-city), was inferred. The space is made up of three axes, x-axis of horizontal space, y-axis of vertical space, and in the sense that all the space has no exit, z-axis of deeper contradictory space. This thesis started with the decision that is the most suitable work in analyzing the metaphorical relationship between self-defense mechanism and anti-house. There was limitation, however, as the typical characteristics of Japanese animations, pedantic composition and the possibility of broad interpretation, hindered clear verification. Hopefully, this limitation will be overcome by following studies and this study is expected to show the importance of space in interpreting the text of animations, and to serve as database for other creative works.

• Journal of Veterinary Clinics
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• v.19 no.2
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• pp.132-138
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• 2002

Non-human primates are widely used for experimental animal and raised as companion animal in Korea. To establish the electrocadiogram (ECG) of non-human primates that are domestically raised, the author measured bipolar limb leads and augmented unipolar limb leads, after tiletamine/zolazepam (TZ) injection as sedative agents. The amplitudes of P,Q, R,S and T wave and duration time of P wave, QRS complex, PR and QT interval in each lead of ECG were evaluated in 7 non-human primates at 15 minutes after TZ injection, respectively. The amplitude of P wave in I, II,III, aVR, aVL and aVF leads revealed 0.06$\pm$ 0.05,0.14$\pm$ 0.05, 0.1 $\pm$ 0.05,-0.11 $\pm$ 0.06,-0.04$\pm$ 0.04 and 0.12$\pm$ 0.05 mV respectively. The amplitude of Q wave revealed -0.16$\pm$ 0.15, -0.23$\pm$ 0.18, -0.17$\pm$ 0.13, 0.16$\pm$0.13, 0.04$\pm$ 0.09 and -0.2$\pm$0.13 mV, respectively. The amplitude of R wave revealed 0.56$\pm$0.56, 1.24$\pm$ 0.67, 0.92$\pm$0.33, -0.37$\pm$ 1.14, -0.22$\pm$ 0.47 and 1.12 $\pm$ 0.47 mV, respectively. The amplitude of S wave revealed -0.02$\pm$ 0.08, -0.04$\pm$0.06, -0.06$\pm$0.04, 0.02$\pm$0.04, 0.04$\pm$0.09 and -0.04 $\pm$ 0.06 mV, respectively. The amplitude of T wave revealed -0.01 $\pm$ 0.15,-0.02$\pm$ 0.13, 0.01 $\pm$ 0.08, 0.02$\pm$ 0.12, 0.01 $\pm$ 0.11 and -0.03$\pm$ 0.09 mV, respectively. The duration time of P wave revealed 0.05 $\pm$ 0.01, 0.04$\pm$ 0.01, 0.05$\pm$ 0.02, 0.05 $\pm$ 0.02, 0.04$\pm$ 0.01 and 0.04$\pm$ 0.01 sec, respectively. The duration time of QRS complex revealed 0.05 $\pm$ 0.02,0.05$\pm$ 0.01, 0.05 $\pm$ 0.01, 0.04$\pm$ 0.01, 0.05$\pm$ 0.01 and 0.05 $\pm$ 0.01 sec, respectively. The duration time of PR interval revealed 0.08$\pm$ 0.01, 0.07$\pm$0.01,0.08$\pm$ 0.03, 0.08$\pm$0.01, 0.08$\pm$ 0.01 and 0.08$\pm$0.01 sec, respectively. The duration time of QT interval revealed 0.23$\pm$ 0.06, 0.22$\pm$ 0.05, 0.23 $\pm$ 0.06, 0.23$\pm$ 0.06, 0.24$\pm$ 0.05 and 0.22$\pm$ 0.02 sec, respectively. No significant changes were observed in e amplitude of P and T waves. The amplitude of QRS complex in ketamine group was higher than that of TZ group. However, no significant changes were observed in both intra-group and inter-group. There were no significant changes in the duration time of P wave, QRS complex and PR interval obtained from both groups. Also, the duration time of QT interval in TZ group was significantly longer at 30 min.(P< 0.05) an that of 10 minutes after injection. However, significant difference was not found between two groups. The mean cardiac electric axis in ketamine group tended to decrease until 30 min. after injection and then gradually increase. However, mean cardiac electric axis of TZ group was increased until 30 min. after injection and then decreased. But significant differences were not observed between groups. These results suggest that the ECG pattern after TZ injection to non-human primates reared in korea was established. It was also considered that the injection of ketamine and TZ didn't significantly affect on ECG pattern of the non-human primates.

• Economic and Environmental Geology
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• v.28 no.6
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• pp.579-585
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• 1995

The Samkwang mine is Cretaceous gold-silver-bearing deposits located in the western part of the Ogcheon belt The ore deposits have been emplaced within granite gneiss of the Precambrian age. The Au-Ag deposits are hydrothermal-vein type, characterized by arsenic-, gold- and silver-bearing sulphides, in addition to the principal ore-forming sulphides arsenopyrite, galena, sphalerite, chalcopyrite, pyrite and pyrrhotite. Their proven reserves are 355,000 MT, and grades are 8.4 g Au/t and 13.6 g Ag/t. On the basis of their structural characters, the Au-Ag-bearing quartz veins are classified into three types of ore veins; (1) The Main vein shows $N40^{\circ}-80^{\circ}E$ strike and $55^{\circ}-90^{\circ}SE$ dip, (2) the Sangban vein shows E-W strike and $30^{\circ}-40^{\circ}S$ dip, and (3) the Gukseong vein has $N25^{\circ}-40^{\circ}W$strike and $65^{\circ}-80^{\circ}SW$ dip. The emplacements of the ore veins are closely related to the minimum stress axis $({\sigma}_3)$ during the strike-slip movement of the study area. The ore-bearing veins filled with extension fractures during strike-slip movements were sequentially emplaced as follows: I) When ${\sigma}_1$ operates obliquely to NE-series discontinous surface, the Main fault zone $(F_1)$ developes. 2) During the same time, extension fractures ($T_1$ Gukseong veins) take place. 3) When the fault progress continuously, the existing $T_1$, may be high angle and $T_2$ (Daehung vein) developes continuously. 4) When ${\sigma}_1$ changes to sinistral sense, $T_3$ (basic dyke) occurs. 5) When a reverse fault becomes active, the Sangban vein is branched from the Guksabong vein.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.3
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• pp.206-214
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• 2014

This study is to evaluate how different bearing surface angles of abutment screw affect the mechanical stability of the joint in the conical seal design implant system. Materials and Methods: Internal connection type regular implants, two-piece cemented type abutments and tungsten carbide/carbon-coated titanium alloy abutment screws were selected. Titanium alloy screws with conical ($45^{\circ}$) and flat ($90^{\circ}$) head designs which fit on to abutment were fabricated. The abutments were tightened to implants with 30 Ncm by digital torque gauge. The loading was applied once to the central axis of abutment. The mean axial displacement was measured using micrometer before and after the tightening and loading (n = 5). The abutment was tightened to implants with 30 Ncm and T-shape stainless steel crown was cemented. Then the change in the amount of reverse-torque was measured after the repeated loading to the central axis, and the place 5 mm away from the central axis. Compressive bending and fatigue strength were measured at the place 5 mm away from the central axis (n = 5). Results: Both groups showed the largest axial displacement when abutment screw tightening and total displacement was greater in the flat head group compared to conical head group (P < 0.05). However, there were no significant differences in reverse torque value, compressive bending and fatigue strength (P > 0.05). Conclusion: Within the limitations of this study, the abutment screw head design had no effect on two groups regarding the joint stability, however the conical head design affected the settlement of abutment resulting in the reduced total displacement.

• Journal of the Korean Magnetics Society
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• v.15 no.5
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• pp.276-281
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• 2005

We have investigated the effects of an external magnetic field on the growth direction and the grain size of electrochemically prepared CoPtP alloys. Electrodeposited CoPtP alloys were synthesized by appling an external magnetic field with 0 to 1 T to the perpendicular direction of the films. In the electrodeposited CoPtP alloys without external magnetic field, the growth direction of the alloys was mixed by fcc (111) and hop (002), but only hop (002) was observed in the alloys with 1 T external magnetic field. CoPtP alloys were grown as the columnar growth and the grain size increases with growing the alloys. With appling an external field, the grain size of the alloys was controlled less than 20 nm which is smaller than single domain of Co, and the easy axis of alloys, hcp (002) direction, was grown perpendicular to the films up to 200 nm. We could obtain the optimal thickness of the alloys and electrodeposition condition from the above results. Coercivity and squareness of CoPtP alloys taken out-of-plane are 6.1 kOe and 0.9, respectively. The magnetic properties of CoPtP alloys were measured by VSM, and the microstructural characterization and crystalline orientation measurement of the alloys were carried out by TEM and XRD.

• The korean journal of orthodontics
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• v.36 no.5
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• pp.369-379
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• 2006

Objective: The purpose of this study was to find changes in the occlusal plane related to different vertical facial patterns and suggest treatment goals and conduct possible treatment mechanisms. Methods: 60 adult patients (28 males, 32 females) who had been diagnosed as Class 1 skeletal malocclusion and treated without extraction were selected. Patients were divided into three groups; short face type (group 1), average face type (group 2) and long face type (group 3), using the data on normal occlusion of Korean adults. Results: The results were achieved by analyzing cephalometric tracings of each group at pre-treatment, end-treatment and post-treatment (about 1 year recall check). The inclination of the occlusion plane tends to gradually increase as the face becomes longer In group 1, COP-X, FOP-X, L6/L1, MP-L6 were significantly decreased, and L1-FOP was significantly increased during the retention period (T3-T2). Group 2 showed no significant change, In group 3, FOP-X was significantly increased during the retention period (T3-T2). During the retention period, FOP-X showed significant change among each group, especially between group 1 and group 3. Conclusion: These results suggest that changes of occlusal plane inclination according to facial vertical pattern need to be considered during the retention period for intrusion, extrusion, and incisor overbite.

• Journal of Yeungnam Medical Science
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• v.16 no.2
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• pp.296-301
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• 1999

Background: Generally, it is difficult to differentiate uterine malignant mixed M$\ddot{u}$ llerian tumor(MMMT) from endometrial carcinom in radiological and clinical aspects. Our purpose is to investigate MR findings that distinguishes MMMT from endometrial carcinoma. Materials and Methods: We retrogradely evaluated the magnetic resonance imaging findings of pathologically proven 5 cases of malignant mixed M$\ddot{u}$llerian tumor(MMMT) and 14 endometrial carcinomas to know the differential points of these two tumors originating in the endometrial cavity. The size of the mass, presence or absence of myometrial or uterine cervical invasion, growth pattern of the mass, signal intensity and degree and pattern of contrast enhancement were analyzed and compared. Results: The length of the long axis of the MMMT was 1.5-9.0cm(average, 5.7cm) but that of the endometrial carcinoma was 0.5-6.0cm(average, 2.5cm). Invasion of uterine cervix which was found in 3 MMMT cases, dilated the endometrial cavity and the lumen of the uterine cervix and showed the pattern of growing into the external os. Invasion of uterine cervix was found in only one case of endometrial carcinoma. The presence or absence of myometrial invasion, the signal intensity and homogeneity on T1- and T2-weighted images, and the degree and patterns of contrast enhancement showed no significant difference. Conclusion: Any specific finding to differentiate MMMT from endometrial carcinoma was not ascertained. However, MMMT can be suspected if the size of the endometrial mass is greater than 5cm and if the mass dilates the enocervical canal and invades the uterine cervix.