• Korean Journal of Pharmacognosy
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• v.25 no.3
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• pp.209-213
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• 1994

For the investigation of medicinal resources from Taraxacum species, the studies were carried out to evaluate the pharmaco-constituents in the aerial part of Taroxacum hallaisanensis, an endemic plant of Korea. From BuOH fraction of the MeOH extract, compound 1 (protocatechuic acid, $C_7H_6O_4,\;3,4-dihydroxy\;benzoic\;acid)$, compound 2 $[C_{22}H_{31}O_6,\;luteolin-7-O-{\alpha}-_L-rhamnopyranosyl(1{\rightarrow}6)-{\beta}-_D-glucopyranoside]$, and compound 3 $[C_{15}H_{20}O_6,\;luteolin-7-O-{\beta}-_D-glucopyranoside]$ were isolated by column chromatographic separation using polyamide and ODS-gel. The structures were elucidated by means of physico-chemical evidences($^1H-NMR,\;{12}^C-NMR$, IR, EI-Mass, FAB-Mass and GC).

• Korean Journal of Heritage: History & Science
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• v.42 no.2
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• pp.86-109
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• 2009

Mireuksa Temple was founded during the reign of King Mu of Baekje(AD 600-641). The circumstance of the construction of this temple is documented in "Memorabilia of the Three Kingdoms (Samgukyusa)". The pagoda named stone pagoda at Mireuksaji temple stands outside the main sanctuary of the western area. The south and west sides of the stone pagoda have completely collapsed, leaving only the eastern facade of six of its levels intact. Through the recent discovery of sarira reliquary we can see that the erection of this pagoda was in 639. So owing to accumulation of excavation results about Baekje temple site and vigorous academic exchange, it is possible that architecture of western pagoda at Mireuksaji temple can be understood in connection with the architectural development of wooden pagoda from 6th to early 7th century in East Asia. So this study is on the consideration of building of this pagoda putting first structure of upper part and cross-shaped space in 1st floor. It was considered that the material characteristics as stone could be applied to the temple pagoda architecture of large scale. The results are as follows. First, it had been built in recognition that the outer and inner part of pagoda should be separated. As it is the expression of structural system in temple pagoda architecture of large scale at that time. In pagoda there was a self-erected structure and the members of outer part of it were constructed additionally. Second, in Mireuksaji stone pagoda there is central column with stones. With inner part of pagoda it can be regarded as mixed structural system that constitutes central contral column and inner structural part. And it could be a kind of middle step to more developed structure of whole as wooden pagodas in Japan. Third, as the sarira reliquary was in central column on the first floor, the cross-shaped space could be made. The formation of this space was so on the natural meaning of sarira that the concept as memorial service of graves could be apllied to the pagoda. The style of tomb in Baekje was expressed to the space of 1st floor in pagoda where Sarira had been mstalled. That was not only effective presentation of symbolic space but also easier method in the use of same material.

• Korean Journal of Veterinary Research
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• v.42 no.2
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• pp.131-136
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• 2002

The vertebrae of female African elephant (Loxodonta africana) of twenty-eight years old were observed macroscopically. The result was summarized as follows; the vertebral formula of African elephant was $C_7$ $T_{21}$ $L_3$ $S_4$ $Cd_{21}$. The total length of the vertebral column removed intervertebreal disks was 353 cm. The length of each segment of vertebral column was 44 cm in cervical, 142 cm in thoracic, 21 cm in lumbar, 27 cm in sacral and 119 cm in caudal vertebrae. The 17th and 18th thoracic vertebrae (T) were partially fused each other in four parts: the transverse processes of 17th and 18th T, caudal articular process of 17th T and cranial articular process of 18th T, left mammilary process of 18th T and left transverse process of 17th T, and vertebral arch of 17th and 18th T, respectively. Others partial fusions also observed among the third luwbar, sacrum and ilium. These were in between transverse process of third lumbar vertebra and cranial parts of wing of sacrum, lateral part of sacrum and tuber sacrale, respectively. The sternum was consisted of three pieces; one is a part of anterior prestemum, two is the part from caudal demifacet at second facet to cranial demifacet at third facet in middle mesosternum, which is divided vertically into an half at second and third facets, respectively, and the last is the part between caudal demifacet of third facet in middle mesosternum and the posterior xiphisternum. There are 21 pairs of ribs, six sternal, ten asternal ribs and the last five being floating ribs.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.507-517
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• 2020

Several methods including morphometric analysis were used to distinguish small yellow croaker (Larimichthys polyactis) from yellow croaker (Larimichthys crocea), which have very similar external shapes. Morphometric analysis showed four considerable differences (p<0.05) among the total 48 morphometric dimensions, but no differences were seen in the classical dimensions (p>0.05). Rather, significant differences were seen in two truss dimensions: Insertion of dorsal fin base - origin of pectoral fin base and origin of anal fin base - origin of pectoral fin base, and two head part dimension: most anterior extension of the head - above of eye and above of eye - posterior aspect of operculum(p<0.05). However, the yellow croaker had higher values than the small yellow croaker in the other three morphometric dimensions except for the head part dimension of above of eye - posterior aspect of operculum of the four morphometric dimensions (p<0.05). The X-ray photographs indicated that the small yellow croaker (45.1±2.34°) had 8.4% more curved vertebral column than the yellow croaker(38.4±1.82°). A diamond-shaped cranium was found when the skin was peeled off from both fish but the commonly held fact that only the small yellow croaker has a diamond-shaped cranium is not accurate. Our results confirmed that the two fish could be definitely distinguished by their external body shape.

• Steel and Composite Structures
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• v.30 no.2
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• pp.97-108
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• 2019

This paper presents a new model for the strap combined footings to obtain the most economical contact surface on the soil (optimal dimensioning) to support an axial load and moment in two directions to each column. The new model considers the soil real pressure, i.e., the pressure varies linearly. Research presented in this paper shows that can be applied to the T-shaped combined footings and the rectangular combined footings. The classical model uses the technique of test and error, i.e., a dimension is proposed, and subsequently, the equation of the biaxial bending is used to obtain the stresses acting on each vertex of the strap combined footing, which must meet the conditions following: The minimum stress should be equal or greater than zero, and maximum stress must be equal or less than the allowable capacity that can withstand the soil. Numerical examples are presented to obtain the optimal area of the contact surface on the soil for the strap combined footings subjected to an axial load and moments in two directions applied to each column. Appendix shows the Tables 4 and 5 for the strap combined footings, the Table 6 for the T-shaped combined footings, and the Table 7 for the rectangular combined footings.

• Geomechanics and Engineering
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• v.14 no.1
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• pp.51-60
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• 2018

The foundations are classified into shallow and deep, which have important differences: in terms of geometry, the behavior of the soil, its structural functionality, and its constructive systems. The shallow foundations may be of various types according to their function; isolated footings, combined footings, strip footings, and slabs foundation. The isolated footings are of the type rectangular, square and circular. The combined footing may be rectangular, trapezoidal or T-shaped in plan. This paper presents a new model for T-shaped combined footings to obtain the most economical contact surface on the soil (optimal dimensioning) to support an axial load and moment in two directions to each column. The new model considers the soil real pressure, i.e., the pressure varies linearly. The classical model uses the technique of test and error, i.e., a dimension is proposed, and subsequently, the equation of the biaxial bending is used to obtain the stresses acting on each vertex of the T-shaped combined footing, which must meet the conditions following: The minimum stress should be equal or greater than zero, and maximum stress must be equal or less than the allowable capacity that can withstand the soil. To illustrate the validity of the new model, numerical examples are presented to obtain the minimum area of the contact surface on the soil for T-shaped combined footings subjected to an axial load and moments in two directions applied to each column.

• Earthquakes and Structures
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• v.7 no.5
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• pp.735-751
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• 2014

In the previous paper, authors proposed the unified equivalent frame method (UEFM) for the lateral behavior analysis of the flat plate structure subjected to the combined gravity and lateral loads, in which the rotations of torsional members were distributed to the equivalent column and the equivalent slab according to the relative ratio of gravity and lateral loads. In this paper, the lateral behavior of the multi-span flat plate structures under various levels of combined gravity and lateral loads were analyzed by the proposed UEFM, which were compared with test results as well as those estimated by existing models. In addition, to consider the stiffness degradation of the flat plate system after cracking, the stiffness reduction factors for torsional members were derived from the test results of the interior and exterior slab-column connection specimens, based on which the simplified nonlinear push-over analysis method for flat plate structures was proposed. The simplified nonlinear analysis method provided good agreements with test results and is considered to be very useful for the practical design of the flat plate structures under the combined gravity and lateral loads.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.421-424
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• 2006

This study, in order for perceiving the mechanical attribute followed by the explosive spalling of high strength concrete material under high temperature and evaluating capacity of endurance of material, targets understanding capacity of endurance of material such as explosive spalling in high temperature, temperature by thickness of clothing, transformation extent, transformation speed and displacement, stocking the maximum load based on the Allowable Stress Design Method. As a result of experimenting the explosive spalling attribute of high strength concrete material, the one possibly causing serious damage is the 50 MPa concrete. In all aspects of 60 MPa concrete, explosive spalling happens. Especially, it is hazardous enough to reveal all the iron bar. All explosive spalling is intensively concentrated on the surface of concrete for the first $5{\sim}25$ minutes, which urges for the explosive spalling protection action. As a result of evaluating the structural safety by the transformation of high strength concrete, while beam assures the fire safety meeting regulation, 60 MPa shows the dramatic increase of transformation, which only counts 84% of safety. In a column, both the concrete exclusion and excessive explosive spalling are concentrated upper part of column, which brings about the dramatic transformation, so it only meets the 50% of safety regulation. Likewise, in 80, 100 MPa concrete which was never experimented considering the condition of domestic structural endurance stocking devices, the faster collapse is expected.

• Advances in environmental research
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• v.4 no.2
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• pp.105-117
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• 2015

The groundwater is a very important part of the environment and must be protected for the benefit of the present and future generation. The contamination of soil and groundwater by chemicals has become an increasing concern in the recent past. These chemicals enter the groundwater system by a wide variety of mechanisms, including accidental spills, land disposal of domestic and industrial wastes and application of agricultural fertilizers. Once introduced into an aquifer, these contaminants will be transported by flowing groundwater and may degrade water quality at nearby wells and streams. For improving the management and protection of groundwater resources, it is important to first understand the various processes that control the transport of contaminants in groundwater. Predictions of the fate of groundwater contaminants can be made to assess the effect of these chemicals on local water resources and to evaluate the effectiveness of remedial actions. In this study, an attempt has been made to investigate the behaviour of solute transport through porous media using laboratory experiments. Sodium chloride was used as a conservative chemical in the experiment. During the experiment, pulse boundary condition and continuous boundary conditions were used. Experimental results have been presented for conservative solute transport in the sand. The pattern of the break through curve remains almost same in all the cases of varying flow rate and initial concentration of conservative chemical.

• Structural Engineering and Mechanics
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• v.86 no.4
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• pp.503-518
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• 2023

In tall constructions, the outriggers are regarded as a structural part capable of effectively resisting lateral loads. This study analyses the efficacy of hybrid outrigger system in high rise RCC building for various structural parameters identified. For variations in α, which is defined as the ratio of the relative flexural stiffness of the core to the axial rigidity of the column, static and dynamic analyses of hybrid outrigger system having a virtual and a conventional outrigger at two distinct levels were conducted in the present study. An investigation on the optimal outrigger position was performed by taking the results from absolute maximum inter storey drift ratio (ISD_max), roof acceleration (acc_roof), roof displacement (disp_roof), and base bending moment under both wind and seismic loads on analytical models having 40, 60 and 80 storeys. An ideal performance index parameter was introduced and was utilized to obtain the optimal position of the hybrid outrigger system considering the combined response of ISD_max, acc_roof, disp_roof and, criteria required for the structure under wind and seismic loads. According to the behavioural study, increasing the column area and outrigger arm length will maximise the performance of the hybrid outrigger system. The analysis results are summarized in a flowchart which provides the optimal positions obtained for each dependent parameter and based on ideal performance index which can be used to make initial suggestions for installing a hybrid outrigger system.