• Journal of Positioning, Navigation, and Timing
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• v.13 no.1
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• pp.85-92
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• 2024

This study develops a Global Positioning System (GPS) Code Multipath Grid Map (CMGM) of each individual domestic reference station from the extracted code multipath of measurement data. Multipath corresponds to signal reflection/refraction caused by obstacles around the receiver antenna, and it is a major source of error that cannot be eliminated by differencing. From the receiver-independent exchange format (RINEX) data for two days, the associated code multipath of a satellite tracking arc is extracted. These code multipath data go through bias correction and interpolation to yield the CMGM with respect to the azimuth and elevation angles. The effect of the CMGM on multipath mitigation is then quantitatively analyzed to improve the Root Mean Square (RMS) of averaged pseudo multipath. Furthermore, the single point positioning (SPP) accuracy is analyzed in terms of the RMS of the horizontal and vertical errors. During two weeks in February 2023, the RMSs of the averaged pseudo multipath for five reference stations decreased by about 40% on average after CMGM application. Also, the SPP accuracies increased by about 7% for horizontal errors and about 10% for vertical errors on average after CMGM application. The overall quantitative analysis indicates that the proposed approach will reduce the convergence time of Differential Global Navigation Satellite System (DGNSS), Real-Time Kinematic (RTK), and Precise Point Positioning (PPP)-RTK correction information in real-time to use measurement data whose code multipath is corrected and mitigated by the CMGM.

• Korean Institute of Interior Design Journal
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• no.21
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• pp.107-113
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• 1999

The purpose of this study is to suggest the materials for developing the new house style by analysing the space characteristics of wood frame houses in suburbs of Seoul. For this, we analysed 45 drawings(site plan, floor plan, elevation, section) that were designed by MICHOO, WOOD-LAND, STUGA and CHOWONJUTECK company etc. The space design characteristics that we found are as follows; 1. The wood is fragile to humidity. Therefore this characteristic is especially considered in designing the space of bathroom and utility room. 2. It is the merit of wood frame house that inner space can be designed variously by using spilt-level and the slope of roof. 3.The public space and private space are completely separated in most cases and the stair is located in the middle of house. This structure of house is short of horizontal openness. Instead, most houses gets vertical openness by making second floor on the living room opev. 4. In wood frame house as the rural house, the outer space is well used by setting up deck and balcony. The outer spaces like deck and balcony are usually used as a part of life space in connected with living room, dining room, master bed room and family room. 5. The public spaces like kitchen, living room, dining room and family room are considered so important in design that those are arranged in front in order to have good outlook and directiov.

• Journal of Environmental Impact Assessment
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• v.17 no.6
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• pp.349-356
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• 2008

This paper aims to understand the effects of a turbidity flow intrusion on eutrophication in Daecheong Dam Reservoir. CE-QUAL-W2, a two-dimensional hydrodynamic and water quality model, is applied. The elevation of the reservoir water surface is used to validate the hydrodynamic model parameters and maximum fluctuations in the water surface elevations reaches about 1 m in the reservoir. During the heavy storm season, July, the thermocline submerged to less than 30 m below the surface. The thickness of the thermocline also reduced to 10 to 15 m. While the average TSS in June, the beginning of the monsoon was still low but it peaked in July due to heavy rainfall. Vertical profiles of the TSS regime in July indicated higher concentration in upper water layers and then the regime moves gradually downward in accordance with the time lapse. Due to the dam spillway opening, high concentrations of TSS attributed to storm turbidity ascended to the upper water layer by following the upward current movement and then, the regime precipitated to a layer below 30 to 40 m after September.

• Journal of Advanced Research in Ocean Engineering
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• v.3 no.2
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• pp.53-58
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• 2017

This study introduces the case of pipelines installed in subsea conditions and buried offshore. Such installations generate pore water pressure under the seabed because of cyclic wave excitation, which is an environmental load, and consistent cyclic wave loading that reduce the soil shear strength of the seabed, possibly leading to liquefaction. Therefore, in view of the liquefaction of the seabed, stability of the subsea pipelines should be examined via calculations using a simple method for buried subsea pipelines and floating structures. Particularly, for studying the possible liquefaction of the seabed in regard to subsea pipelines, high waves of a 10- and 100-year period and the number of occurrences that are affected by the environment within a division cycle of 90 s should be applied. However, when applying significant wave heights (HS), the number of occurrences within a division cycle of 3 h are required to be considered. Furthermore, to research whether dynamic vertical load affect the seabed, mostly a linear wave is used; this is particularly necessary to apply for considering the liquefaction of the seabed in the case of pile structure or subsea pipeline installation.

• Korean Institute of Interior Design Journal
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• v.24 no.1
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• pp.64-71
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• 2015

This study aims to disclose the dynamics of Daniel Libeskind Museums by the principles of counterbalance. Balance as a dynamic concept is the settlement of instability and tension and to draw overall sense of balance by controlling new perception elements that may cope with the unbalance elements. This is based on balancing compensation and can be explained as a counterbalance. Daniel Libeskind, a representative architect of deconstructivism, creates dynamic space by using oblique lines on the plane. The study was carried out under the assumption that this space would be designed under the certain principles rather than the result of momentary feelings and the analysis was conducted by the counterpoint of music and counterbalance. As a result, Daniel Libeskind balances in a way of forming the mutual right angle by using oblique lines which cancel out the unbalance in plane composition or making the same angle based on vertical / horizontal axis. Counterbalance has been achieved in the section and elevation as well as plane and complex and diverse oblique lines were worked under the constant principle not accidental results. The axes of Daniel Libeskind's architecture have been known to follow contextualism with symbolism and historicity but it was found that a design technique considering counterbalance was used in the overall control.

• Earthquakes and Structures
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• v.11 no.3
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• pp.421-443
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• 2016

When conducting seismic assessment of an asymmetric building, it is essential to carry out three-dimensional analysis considering all the possible directions of seismic input. For this purpose, the author proposed a simplified procedure is to predict the largest peak seismic response of an asymmetric building subjected to horizontal bidirectional ground motion acting in an arbitrary angle of incidence in previous study. This simplified procedure has been applied to torsionally stiff (TS) asymmetric buildings with regular elevation. However, the suitability of this procedure to estimate the peak response of an asymmetric building with vertical irregularity, such as an asymmetric building with setback, has not been assessed. In this article, the pushover-based simplified procedure is applied to estimate the peak response of asymmetric buildings with bidirectional setback. Nonlinear dynamic (time-history) analysis of two six-storey asymmetric buildings with bidirectional setback and designed according to strong-column weak beam concept is carried out considering various directions of seismic input, and the results compared with those estimated by the proposed method. The largest peak displacement estimated by the simplified method agrees well with the envelope of the dynamic analysis response. The suitability assessment of the simplified procedure to analysed building models is made as well based on pushover analysis results.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.3
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• pp.117-122
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• 2014

Objectives: The purpose of this study was to evaluate the sinus bone graft resorption over 3 years after two-stage implant placement. Materials and Methods: The subjects for this study included 30 patients whose maxillary posterior ridges were too atrophic for implants. Bone-added osteotome sinus floor elevation was used in 15 maxillary sinuses, while the bone graft by lateral approach technique was used in 25 maxillary sinuses. The height from the top of the fixture to the sinus floor was estimated immediately after implant placement and the follow-up period was over 3 years. The surgery was classified with two groups: sinus bone grafting with and without autogenous bone. All implants were placed simultaneously. Results: The mean vertical bone loss was $3.15{\pm}2.95mm$. The survival rate of implants was 94.7%. Conclusion: The amount of bone resorption was not significantly associated with the surgical methods, the type of bone graft materials used, or sinus perforation during surgery.

• Journal of the Korean housing association
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• v.24 no.6
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• pp.133-140
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• 2013

This study is to clarify the form of window and door of medieval times house which are no longer in existence, by comparative analysis between literature materials and architectural remains of united Silla and Goryo period. Particularly the window and door form change process of was analyzed, in connection with the change of term which are recorded in literature material. The form and the composition of window and door are the elements which determine the elevation design of architecture and concerned with interior environment. Therefore this study is significant in the sense that it could be used as base data for the study on the reconstruction and interior space of medieval times house. There were ho (戶) and moon (門) as door, and chang (窓) for lighting and ventilation as window. Among these, the window can be divided into fixed and openable. There were two kind of fixed window. One is called chang (窓), and it was covered by silk or paper for lighting. The other is called ham (檻), it was the form of vertical bar window and lighting and ventilation was available. And there were two kind of openable window. One is called ho (戶), which had wooden plate window leaves. And the other is called changho (窓戶), lighting was available in the condition of closing.

• Journal of Periodontal and Implant Science
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• v.40 no.6
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• pp.271-275
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• 2010

Purpose: Many techniques have been described for achieving vertical augmentation of the maxillary sinus. The aim of this study is to evaluate the effect of low-intensity pulsed ultrasound (LIPUS) to enhance bone regeneration after sinus floor elevation. Methods: The sinus lifting technique was performed through a lateral approach on 8 different sites of 5 patients (3 males and 2 females) and their mean age was 45.7 years old. The sites were randomly assigned to the control or test groups. The control group had 4 sites that received lateral sinus lifting procedure only, while the test group had 4 sites that received LIPUS application after the lateral sinus lifting procedure. 24-32 weeks (an average of 29 weeks) postoperatively, new bone formation in the augmented sinus sites was evaluated through histologic and histomorphometric analyses of the biopsy specimens obtained during implant placement. Results: In the test group, the mean percentage of newly formed bone was $19.0{\pm}2.8$%. In the control group, the mean percentage of newly formed bone was $15.2{\pm}3.1$%. The percentage of newly formed bone was approximately 4% higher in those cases where the sinus was treated by LIPUS than the percentage in those cases where it was not used. The difference was statistically significant. Conclusions: Within the scope of this study, low-intensity pulsed ultrasound application after sinus lifting appeared to have a significant effect on the development of new bone formation.

• International Journal of High-Rise Buildings
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• v.7 no.3
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• pp.255-264
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• 2018

This paper introduces three distinctive means for the use of a 189-meter high damped structure ensuring safety against earthquake: 1. Realization of L-shaped elevational structural planning: The bottom and top of the tower have belt trusses and hat trusses respectively to restrain the bending deformation. Furthermore, large-capacity oil dampers (damping force 6,000 kN) are installed in the middle part of the tower to restrain the higher-mode deformation. 2. Realization of L-shaped planar structural planning: We devised a means of matching the centers of gravity and rigidity by adjusting planar rigidity. Moreover, viscous damping devices are located at the edges of the L-shaped plan, where torsional deformation tends to be amplified. We call this the "Damping Tail" system. 3. Composite foundation to equalize deformations under different loading conditions: We studied the vertical and horizontal deformations using sway-rocking and 3D FEM models including the ground, and applied multi-stage diameter-enlarged piles to the tower and a mat foundation to the podium to keep the foundations from torsional deformations and ensure structural safety.