• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.11a
• /
• pp.73-74
• /
• 2007

• Journal of the Korean GEO-environmental Society
• /
• v.24 no.5
• /
• pp.21-28
• /
• 2023

In this paper, an experimental study was conducted to present the properties of rapid hardening composite mat, and a numerical analysis was carried out to analyze the slope protection effect of the mats based on ground conditions, rainfall, slope gradient and soil height. As a result, the application of rapid hardening composite mat increased the slope safety factor in all conditions, and the increase rate of safety factor showed an average of 40% increase both in dry and rainy seasons. Through these research findings, the protective effect of the rapid hardening composite mat on sloping surfaces has been proven, and it is suggested that the rapid hardening composite mat is suitable for application in areas where slope failure or collapse is expected.

• Proceedings of the KSR Conference
• /
• 2008.06b
• /
• pp.27-41
• /
• 2008

Construction of metro transportation infra is a large-scale project requiring tremendous financial resources. This study suggests operation method to use for rapid transit line existing infra such as Gyeongbu line and spare line capacity following second phase KTX construction. Reviewing various constraints of metro rapid transit operation, we found that the conditions for metro rapid transit operation are already satisfied in Daegu area, just like the case of Gyeongbu line in Seoul Metro area. Also, the evaluation of the economic feasibility of metro rapid transit operation in Daegu area shows that B/C is about 2.4, which implies that there is sufficient economic feasibility. According to the result of sensitivity analysis, the project is economically feasible unless the passenger demand decreases 15% and construction costs increases more than 70%. B/C is evaluated large because the utilization of already exiting infra lowers the initial cost. As one of mass transportation system of large capacity, metro rapid transit can generate significant spillover effect: It will strengthen competitiveness of metro area by connecting cities within the area and by extending one-day life zone of the area, to say nothing of the benefit of improving traffic condition. The construction of metro rapid transit network is necessary for the mass transportation system of Yeongnam area as well as Daegu area, and it may work as a starting point for uniting Daegu and Gyeongbuk and strengthening regional competitiveness.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.21 no.4
• /
• pp.309-316
• /
• 2003

Rapid and accurate data processing is required in many GPS(Global Positioning System) applications including surveying. While one can use four different kinds of GPS satellite orbits, we evaluated the accuracy and precision of each kind of orbits to find the best candidate for rapid and accurate data processing. The four different kinds of orbits we: broadcast orbits from GPS satellites; and ultra-rapid orbits, rapid orbits, and precise orbits provided by international GPS data analysis centers such as IGS. With GIPSY and ultra-rapid orbits, we could get the positioning accuracy of 1.5cm from seven days of GPS data. From this study, we conclude that rapid and accurate data processing is achieved with GIPSY and ultra-rapid orbits.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.38 no.1
• /
• pp.66-71
• /
• 1993

Several trials and errors were repeated to develop a simplified recipe of amylose analysis using a Rapid Flow Autoanalyzer(Alpkem, RFA-300). The amylose content of rice samples analyzed by the Rapid Flow Autoanalyzer were compared with those of Williams’ and Juliano’s assay. The results by the simplified recipe of RFA amylose analysis were highly correlated with those by Williams’ and Juliano’s method(r=0.95$^{**}$-0.97$^{**}$). The relative amylose content of defatted rice starch was higher than those of non-defatted rice flour, showing very close correlations between those analyzed by three method.

• Journal of Korean Association for Spatial Structures
• /
• v.11 no.2
• /
• pp.55-62
• /
• 2011

While frequency of occurrence of terrorism has recently increased, it intensively occurs in buildings that many unspecified persons gather. Terrorism which occurs in high-rise buildings causes a lot of damage. It is necessary for design approach to reduce terrorism damage from explosive of buildings. Terror risk analysis of domestic tall and high-rise buildings is evaluated by fema 455, Rapid Visual Screening which is found to be comparatively simple and practicable. Common risk factors of terrorism in domestic buildings were investigated. The results of terror risk assessment of all buildings are found to be a medium risk score, Main reason is that domestic tall or high-rise buildings have similar external-environmental factors.

• Structural Engineering and Mechanics
• /
• v.48 no.2
• /
• pp.257-274
• /
• 2013

In this study, seismic performance of one story hinged precast buildings, which represents the majority of existing lightweight industrial building stock of Turkey, was assessed. A lot of precast buildings, constructed in one of the important seismic zones of western Turkey, were investigated and building inventories were prepared. By this method, structural properties of inventory buildings and damaged precast buildings in recent earthquakes were compared. Damage estimations based on nonlinear analysis methods have shown that estimated damage levels of inventory buildings and observed damage levels in recent earthquakes are similar. Accuracy of damage estimation study and the simplicity of the one story precast building models implied that rapid seismic performance assessment method for these buildings can be developed. In this assessment method, capacity curves and vibration periods of precast buildings were calculated by using structural properties of precast buildings. The proposed assessment method was applied to inventory buildings by using two different seismic demand scenarios which reflect moderate and soft soil conditions. Comparison of detailed analysis and rapid assessment methods have indicated that reliable seismic performance estimations can be performed by using proposed method. It is also observed that distribution of damage estimations is compatible in both scenarios.

• Journal of the Korean Society for Precision Engineering
• /
• v.25 no.11
• /
• pp.126-133
• /
• 2008

Rapid Prototyping (RP) has been widely used for rapid development of prototypes in various industrial fields. In recent years, a new requirement in RP industry has issued so as to directly manufacture a functional prototype which has enough mechanical properties to be used as a functional part. The RP prototype, however, has a limitation in mechanical properties due to its layer-by-layer manufacturing process. This manufacturing process results in anisotropy of the prototype, especially showing weakness in the building direction. In the present work, we performed tensile tests for RP prototypes in order to determine directional mechanical properties. The test specimens were made by using $Eden330^{TM}$ by Object Geometries Ltd. Finite element analyses considering material anisotropy were then carried out for RP prototypes with various building directions. Effect of the building direction on the mechanical strength was investigated through the analysis, and compared with experimental results.

• Journal of Ginseng Research
• /
• v.12 no.2
• /
• pp.164-172
• /
• 1988

The solvent separation step in the conventional method for quantitative analysis of ginsenosides was substituted by purification through a small reverse-phase $C_18$-column resulting in the decrease of analysis time by one fourth. New method showed high recovery of total ginsenosides but low recovery in protopanaxatriol-ginsenosides. Sugars did not affect the recovery by the amount in usual root sample. Coefficient of variation in recovery of ginsenosides was lower in the rapid minicolumn method. Optimum load of ginsenosides to minicolumn was 10 to 15 mg. The rapid minicolumn method showed highly significant correlation with the solvent separation method for dried root and red ginseng. For the rapid minicolumn method a small acryl device was used for the simultaneous extraction of 8 samples. This method appeared to be beneficial in cost and for the health of analyst.

• The korean journal of orthodontics
• /
• v.15 no.1
• /
• pp.43-54
• /
• 1985

Recently, rapid palatal expansion technique is widely used for the correction of the skeletal imbalance in Cl III malocclusion patients. There were many studies about the cephalometric changes to rapid palatal expansion but quantitative analysis were small. The purpose of this study was to analysis the stresses and displacement of the maxilla in human dry skull to rapid palatal expansion. The results were as follows: 1. The anterior portion of palate show more lateral and inferior displacement than the posterior portion. But the posterior portion show more anterior displacement. 2. In transpalatal suture area, the medial portion show more anterior and inferior displacement than the lateral portion. But the lateral portion show more lateral displacement than the medial portion. 3. In mid-sagittal plane, the lower portion (palatal area) of maxilla show more anterior, lateral, inferior displacement than the upper portion (frontamaxillary stuture area). 4. In zygomatic arch, the adjacent area to maxilla show tonsil. stresses and the adjacent area to frontal bone show compressive stresses. 5. The sequence of stress bearing area to R.P.E. is upper retromolar area, upper 1st molar, 1st premolar, 2nd premolar, anterior segment of teeth.