• Journal of Astronomy and Space Sciences
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• v.16 no.2
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• pp.167-176
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• 1999

The optimal initial inclination for minimizing the variation of the Local Time of Ascending Node(LTAN) during the three year mission of the KOMPSAT is investigated. At first, the analytical equation for the inclination change by the Sun is derived and the optimal initial inclination by analytical method is derived. Then the analytically derived optimal inclination is checked by the numerical orbit propagation with including all major perturbations. Four different cases of the initial orbital elements are used for monitoring the LTAN variation of the LTAN. Therefore, a new optimal initial inclination by numerical orbit propagation for the KOMPSAT is found. In addition, the variations of the mean and osculating semi-major axis are investigated with the different atmospheric density values. The mean eccentricity vs. argument of perigee diagram for the frozen orbit is obtained.

• The korean journal of orthodontics
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• v.52 no.6
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• pp.387-398
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• 2022

Objective: Controlling the incisal inclination is fundamental in orthodontics. However, the relationship between the inclination prescription and its clinical outcome is not obvious, and the incisal inclination changes generated by different bracket prescriptions were investigated. Methods: Twenty-eight non-extraction dental Class II patients (15 females, 13 males; mean age = 12.9) were retrospectively analyzed. Patients were treated using passive self-ligating fixed appliances with three inclination prescriptions for maxillary incisors (high, standard, low), and two for mandibular incisors (standard, low). Clinical outcomes were compared among different prescriptions, and regression analysis was used to explain the effects of bracket prescriptions and to understand the prescription selection criteria (α = 0.05). Results: For maxillary central incisors, low and high prescriptions were related to linguoversion (p = 0.046) and labioversion (p = 0.005), respectively, while standard prescription maintained the initial dental inclination. Maxillary lateral incisors did not show significant changes. For mandibular incisors, low prescription led to linguoversion (p = 0.005 for central incisors, p = 0.010 for lateral incisors), while standard prescription led to labioversion (p = 0.045 for central incisors, p = 0.005 for lateral incisors). The factors affecting inclination changes were the imposed change and selected prescription, while prescription selection was influenced by the initial dental inclination and initial intercanine distance. Conclusions: The direction of correction of incisal inclination can be controlled by choosing a certain prescription, but the final inclination may show limited consistency with it. The amount of imposed inclination change was the most relevant predictor of the clinical outcome.

• Physical Therapy Korea
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• v.13 no.2
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• pp.16-25
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• 2006

The aim of this study was to investigate the kinematics of young adults during descent ramp climbing at different inclinations. Twenty-three subjects descended four steps at four different inclinations (level, $-8^{\circ}$, $-16^{\circ}$, $-24^{\circ}$). The 3-D kinematics were measured by a camera-based Falcon System. The data were analyzed using one-way ANOVA and the Student-Newman-Keuls test. The kinematics of descent ramp walking could be clearly distinguished from the kinematics of level walking. On a sagittal plane, the ankle joint was more plantar flexed at initial contact with $-16^{\circ}/-24^{\circ}$ inclination, was decreased in the toe off position with all inclinations (p<.001),and was decreased at maximum plantar flexion during the swing phase (p<.001). The knee joint was more flexed at initial contact with the $-24^{\circ}$ inclination (p<.001), was more flexed in the toe off position with all inclinations (p<.001), and was more flexed at minimum flexion during stance phase and at maximum flexion during swing phase with $-16^{\circ}$, $-24^{\circ}$ inclination (p<.001). The hip joint was more flexed in the toe off position with $-16^{\circ}$, $-24^{\circ}$ inclination and was deceased at maximum extension during stance phase with $-16^{\circ}$, $-24^{\circ}$ inclination (p<.05). In the frontal plane, the ankle joint was more everted at maximum eversion during stance phase with $-16^{\circ}/-24^{\circ}$ inclination (p<.01) and was decreased at maximum inversion during swing phase with $-16^{\circ}$, $-24^{\circ}$ inclination (p<.01). The knee joint was more increased at maximum varus during stance phase with $-16^{\circ}/-24^{\circ}$ inclination (p<.001). The hip joint was deceased at maximum adduction during stance phase with $-24^{\circ}$ inclination (p<.05). In a horizontal plane, only the knee joint was increased at maximum internal rotation during stance phase with $-24^{\circ}$ inclination (p<.05). In descent ramp walking, the different gait patterns occurred at an inclination of over $16^{\circ}$ on the descending ramp in the sagittal and frontal planes. These results suggest that there is a certain inclination angle or angular range where subjects do switch between level walking and descent ramp walking gait patterns.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.81-84
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• 2001

An inverse finite element approach is employed for more capability to design the optimum blank shape from the desired final shape with small amount of computation time and effort. In some drawing or stamping simulation with inverse method, it is difficult to apply inverse scheme due to the large aspect ratio or steep vertical angle of inclination. The reason is that initial guesses are hard to make out with present method for those cases. In this paper, a direct mesh marring scheme to generate initial guess on the sliding constraint surface described by finite element patches is suggested for one step inverse analysis to calculate initial blank shape. Radial type mapping is adopted for the simulation of rectangular cup drawing process with large aspect ratio and parallel type mapping for the simulation of S-Rail forming process with steep vertical angle of inclination.

• Journal of Astronomy and Space Sciences
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• v.31 no.4
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• pp.285-294
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• 2014

The uneven mass distribution of the Moon highly perturbs the lunar spacecrafts. This uneven mass distribution leads to peculiar dynamical features of the lunar orbiters. The critical inclination is the value of inclination which keeps the deviation of the argument of pericentre from the initial values to be zero. Considerable investigations have been performed for critical inclination when the gravity field is assumed to be symmetric around the equator, namely for oblate gravity field to which Earth's satellites are most likely to be subjected. But in the case of a lunar orbiter, the gravity field of mass distribution is rather asymmetric, that is, sectorial, and tesseral, harmonic coefficients are big enough so they can't be neglected. In the present work, the effects of the first sectorial and tesseral harmonic coefficients in addition to the first zonal harmonic coefficients on the critical inclination of a lunar artificial satellite are investigated. The study is carried out using the Hamiltonian framework. The Hamiltonian of the problem is cconstructed and the short periodic terms are eliminated using Delaunay canonical variables. Considering the above perturbations, numerical simulations for a hypothetical lunar orbiter are presented. Finally, this study reveals that the critical inclination is quite different from the critical inclination of traditional sense and/or even has multiple solutions. Consequently, different families of critical inclination are obtained and analyzed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.4
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• pp.435-445
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• 1997

It was studied the phenomena of transient freezing of an inclined water-saturated enclosure. One side of the test section was cooled and the other sides were insulated. The effects of the initial temperature, the inclination angle on the temperature field and the shape of the ice-water interface were observed. In the beginning of freezing, with increasing the inclination angle the freezing rate was increased and in the stable density layer centered $4^{\circ}C$, the freezing was fast as the convective fluid flow became small. When the initial temperature was above the $4^{\circ}C$, the frozen thickness in the upper part of inclined surface was thinner than that in the lower part, but with time the frozen thickness of upper part was thicker than that of lower part, below the $4^{\circ}C$, the frozen thickness in the upper part was thicker than that of lower part from the begining, and above the $8^{\circ}C$ in the beginning upper part was thinner with concave, but with time thicker the upper part, vanishing concave.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.6 no.3
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• pp.182-192
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• 1994

This paper focuses on the investigation of the heat transfer phenomena that occur inside the cylindrical tube. The inclination of the tube is adopted as a principal parameter varying from vertical to horizontal. The phase change material employed in this experiment is 99 percent pure n-docosane paraffin($C_{22}$ $H_{46}$). It is found that the amount of solidified mass during a prescribed solidifying period is not sensitive to the inclination of the tube but to the local layer thickness. It is studied that the latent energy is the largest contributor to the total extracted energy. The sensible energy($E_{s1}$, $E_{s2}$, $E_{s3}$) may not be negligible at the large wall-subcooling and initial-liquid-superheating, also at the first step of solidifying.

• The Journal of Korean Physical Therapy
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• v.17 no.4
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• pp.633-650
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• 2005

The aim of this study was to investigate the kinematics of young adults during ascent ramp climbing at different inclinations. Twenty-three subjects ascended a four step at four different inclinations(level, $8^{\circ},\;16^{\circ},\;24^{\circ}$). The 3-D kinematics was analysed by a camera-based falcon system. Groups difference was tested with one -way ANOVA and SNK test. The different kinematic patterns of ramp ascent were analysed and compared to level walking patterns. The kinematics of ramp walking could be clearly distinguished from the kinematics of level walking. In sagittal plane, Ankle joint was more dorsiflexed at initial contact and Max. dorsiflex. during stance phase with $16^{\circ},\;24^{\circ}$ inclination and more plantarflexed at toe off and Max. plantarflex. during swing phase with $24^{\circ}$(p<.001). Knee joint was more flexed at initial contact with $16^{\circ},\;24^{\circ}$ inclination(p<.001). Hip joint was more flexed at initial contact and Max. flex. during swing phase with $16^{\circ},\;24^{\circ}$ inclination and at toe off with $24^{\circ}$(p<.001) and was more extended at Max. ext. during stance phase with $24^{\circ}$(p<.05). In frontal plane, ankle joint was more everted at Max. eversion. during stance phase with $16^{\circ},\;24^{\circ}$ inclination(p<.001). Knee joint was more increased at Max. varus. during stance phase with $16^{\circ},\;24^{\circ}$ inclination(p<.001). Hip joint was not differentiated with different inclinations. In horizontal plane, all joints were not differentiated with different inclinations. Conclusionally, In ascent ramp walking, the different gait pattern generally occurred at over $16^{\circ}$ on the ascending ramp in sagittal and frontal plane. These results suggest that there is a certain inclination angle or angular range where subjects do switch between a level walking and a ascent ramp walking gait pattern. This shows their motor control strategy between level and ascent ramp walking. Further studies are necessary to confirm and detect the ascent ramp gait patterns.

• Wind and Structures
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• v.37 no.5
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• pp.331-346
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• 2023

This work investigates the effects of transverse inclination on an aeroelastic prism through forced-vibration wind tunnel experiments. The aerodynamic characteristics are tri-parametrically evaluated under different wind speeds, inclination angles, and oscillation amplitudes. Results show that transverse inclination fundamentally changes the wake phenomenology by impinging the fix-end horseshoe vortex and breaking the separation symmetry. The aftermath is a bi-polar, one-and-for-all change in the aerodynamics near the prism base. The suppression of the horseshoe vortex unleashes the Kármán vortex, which significantly increases the unsteady crosswind force. After the initial morphology switch, the aerodynamics become independent of inclination angle and oscillation amplitude and depend solely on wind speed. The structure's upper portion does not feel the effect, so this phenomenon is called Base Intensification. The phenomenon only projects notable impacts on the low-speed and VIV regime and is indifferent in the high-speed. In practice, Base Intensification will disrupt the pedestrian-level wind environment from the unleashed Bérnard-Kármán vortex shedding. Moreover, it increases the aerodynamic load at a structure base by as much as 4.3 times. Since fix-end stiffness prevents elastic dissipation, the load translates to massive stress, making detection trickier and failures, if they are to occur, extreme, and without any warnings.

• Journal of Periodontal and Implant Science
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• v.50 no.3
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• pp.146-158
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• 2020

Purpose: The aim of this study was to investigate and identify the main causes of periodontal tissue change associated with labial gingival recession by examining the anterior region of patients who underwent orthodontic treatment. Methods: In total, 45 patients who had undergone orthodontic treatment from January 2010 to December 2015 were included. Before and after the orthodontic treatment, sectioned images from 3-dimensional digital model scanning and cone-beam computed tomography images in the same region were superimposed to measure periodontal parameters. The initial labial gingival thickness (IGT) and the initial labial alveolar bone thickness (IBT) were measured at 4 mm below the cementoenamel junction (CEJ), and the change of the labial gingival margin was defined as the change of the distance from the CEJ to the gingival margin. Additionally, the jaw, tooth position, tooth inclination, tooth rotation, and history of orthognathic surgery were investigated to determine the various factors that could have affected anterior periodontal tissue changes. Results: The mean IGT and IBT were 0.77±0.29 mm and 0.77±0.32 mm, respectively. The mean gingival recession was 0.14±0.57 mm. Tooth inclination had a significant association with gingival recession, and as tooth inclination increased labially, gingival recession increased by approximately 0.2 mm per 1°. Conclusions: In conclusion, the IGT, IBT, tooth position, tooth rotation, and history of orthognathic surgery did not affect labial gingival recession. However, tooth inclination showed a significant association with labial gingival recession of the anterior teeth after orthodontic treatment.