• Korean Journal of Heritage: History & Science
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• v.53 no.3
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• pp.244-257
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• 2020

State-designated rain gauge pedestals, including a rain gauge support, were installed in front of the "Imunwon" at Changdeok Palace, made from various rock types. Some of those pedestals provide exact information on their production dates. These rain gauge pedestals are highly valuable as scientific instruments; however, there has been insufficient scientific research carried out on them. Therefore, precise analysis and conservative consideration are required. As a result of petrographic character analysis, the Changdeokgung rain gauge pedestal has been classified as marble. Furthermore, comparison of the results of P-XRF analysis with GSJ reference samples (JLs-1, JDo-1) has determined it to be dolomitic marble. Applying the same analysis to other state-designated rain gauge pedestals, it was presumed that the rain gauge supports at Gyeongsand-do Provincial Office and Gwansanggam were each made from aplite, pinkish medium-to-coarse biotite granite. Results confirmed that only the Changdeokgung rain gauge pedestal was made from marble. Marble is viewed as having an identity specificity rooted in a certain historical background. According to the tendency towards stone figures being made from marble, especially dolomitic marble, it is necessary to further studies whether particular rocks were used to make royal stone figures in Joseon Dynasty.

• Korean Journal of Cognitive Science
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• v.26 no.3
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• pp.357-375
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• 2015

In our daily life, the probability of target prevalence in visual search varies from very low to high. However, most laboratory studies of visual search used a fixed probability of target prevalence at 50%. The present study examined the properties of information processing during visual search where the probability of target prevalence was manipulated to vary from low (20%), medium (50%), to high (80%). The search items were made of simple shape stimuli, and search accuracy, signal detection measures, and reaction times (RTs) were analyzed for characterizing the effect of target prevalence on the information processing strategies for visual search. The analyses showed that the rates of misses increased whereas those of false alarms decreased in the search condition of low target prevalence, whereas the pattern was reversed in the high prevalence condition. Signal detection measures revealed that the target prevalence shifted response criterion (c) without affecting sensitivity (d'). In addition, RTs for correct rejection responses in the target-absent trials became delayed as the prevalence increased, whereas those for hits in the target-present trials were relatively constant regardless of the prevalence. The RT delay in the target-absent trials indicates that increased target prevalence made the 'quitting threshold' for search termination more conservative. These results support an account that the target prevalence effect in visual search arises from a shift of decision criteria and the subsequent changes in search information processing, while rejecting the account of a speed-accuracy tradeoff.

• Journal of Korean Society of Steel Construction
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• v.9 no.4 s.33
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• pp.543-555
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• 1997

Generally, in a steel-concrete composite gilder, the shear connector which was constructed between concrete deck and steel girder should have enough stiffness to behave as one body, because the conformity between plate and concrete deck is influences by the stiffness and spacing of the shear connectors. If the stiffness of shear connectors are insufficient, slip would happen at the contact surface. Partial interaction is the case that takes account of slips. In this paper, an easy method is presented to evaluate the stiffness or spacing of the shear connector according to the degree of imperfection without difficult calculations for a composite gilder with partial interaction. Also, the horizontal shearing force applied to the shear connector and the longitudinal axial force, which is occurs at contact surface between concrete deck and steel girder, have been presented in a simple influence line that is various to the parameters of sectional properties, degree of imperfection and applied load points. Furthermore, through the case study, it determined the relationships between the degree of imperfection and the follows 1) spring constants 2) axial force and horizontal shearing force 3) stress and neutral axis by using the partial differential equation based on Newmark's Partial Interaction Theory.

• The Journal of Engineering Geology
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• v.11 no.3
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• pp.315-325
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• 2001

A series of laboratory tests was conducted to observe damage process by stress and to understand characteristics of permeability related with rock damage. Rock specimens which were composed of the Cretaceous medium grained granites were experienced of damage stress between 65% and 95% of the compressive strength. Rock deformation by damage process was identified with the elastic wave velocity test. Relationship between rock damage and permeability change was also analyzed by water injection test in the laboratory. According to the results of the tests, damage tends to be occurred from stress level of 80% of the compressive strength and it reduces elastic wave velocity. The damaged specimens with stress more than 80% of the compressive strength showed crack density more than 0.6 and persistent length with good connectivity of cracks. They also have higher permeability than that of specimens with crack density less than 0.6. Considered with the above results, the rock specimens used in this study were fully damaged from stress level of 80% of the compressive strength. Crack initiation and propagation by damage caused good connectivity of cracks through rock specimen. These damage process, therefore, brought high permeability coefficient through water flow conduit in the rock specimen.

• The Journal of the Acoustical Society of Korea
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• v.24 no.8
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• pp.481-491
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• 2005

The purpose of this study is to interpret the evaluation structure of auditory images about streetscapes in urban area on the basis of the semantic view of soundscapes. Using the caption evaluation method. which is a new method, from 2001 to 2005, a total of 45 college students participated in a fieldwork to find out the images of sounds while walking on the main streets of Namwon city. It was able get various data which include elements, features, impressions, and preferences about auditory scene. In Namwon city, the elements of the formation of auditory images are classified into natural sound and artificial sound which include machinery sounds, community sounds. and signal sounds. Also, the features of the auditory scene are classified by kind of sound, behavior, condition, character, relationship of circumference and image. Finally, the impression of auditory scene is classified into three categories, which are the emotions of humans, atmosphere of the streets, and the characteristics of the sound itself. From the relationship between auditory scene and estimation, the elements, features and impressions of auditory scene consist of the items which are positive, neutral, and negative images. Also, it was able to grasp the characteristics of auditory image of place or space through the evaluation model of streetscapes in Namwon city.

• The Journal of the Petrological Society of Korea
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• v.18 no.3
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• pp.211-221
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• 2009

This study illustrates the relationship between the petrographic characteristics of micrographic granite and the topographic features around Ijin-ri. Light-brown to light- gray granite is composed of intergrown fine-grained quartz + orthoclase, displaying micrographic textures. Miarolitic cavities are abundant. Many micro-landforms including tor, tafoni, and gnamma occurred in the micrographic granite of the study area. Tafoni is dominant in the north and gnamma is dominant in south. From our study of the occurrence and textural properties, two alteration zones were clearly identified; one is an external zone (A) characterized by abundant of small sized miarolitic cavities and the other is an internal zone (B) having them less than zone A. The former is dominant in north, and the latter is dominant in south. Particular geomorphologic features such as fluting cores and raised rims are present in the Ijin-ri area. This suggests that development of miarolitic cavities played an important role in the formation of the various geomorphologic features. Consequently, the petrogenesis of the micrographic granite is related to geomorphologic features in the external zone typified by abundant tafoni such as the tiger rock, and the formation of a platform as micro-landforms is influenced by thetextural differences of host rock in the internal zone.

• Journal of Conservation Science
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• v.28 no.4
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• pp.329-341
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• 2012

Magai Wareiishi Jizo (Buddhist statue carved on rock surface) is close to shoreline and a part of rock block is periodically immersed by seawater. Rock material of the Wareiishi-jizo statue is composed mainly of medium or coarse-grained biotite granite and very durable. However, physical properties of the rock have been changed according to the complex interactions of the salt solution and surrounding environment. Exfoliation of the rock surface is a serious condition by salt crystallization. Exfoliation (14.6%) is concentrated on the upper part of the rock block with mainly boundary of seawater as the center. On the other hand, lower part of the rock block show black layers by contaminants deposition. In addition, brown discoloration and biological contaminants is overlapped. Rock surface show high discoloration rate of 50.5% (black discoloration, 29.2% > yellow discoloration, 14.1% > brown discoloration, 4.4% > green discoloration, 2.9%). Upper part of the rock block had a lot of change in the physical properties than lower part that is immersed by seawater. In particular, surface properties of the rock block was very weak state at the boundary surface of seawater permeation.

• Iberoamérica
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• v.23 no.2
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• pp.93-134
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• 2021

With the inauguration of the Bolsonaro administration in 2019, Brazil experienced a noticeable transformation in its policy lines at home and abroad. Limiting this change to diplomacy, it can be pointed out that pro-U.S. and anti-China diplomacy, which is clearly distinguished from the previous regimes, has begun in earnest. Nevertheless, the existing literature on this topic is limited, and it is mainly poetic reporting through the media. This paper aims to derive the main determinant of Bolsonaru's pro-U.S. and anti-China diplomatic lines by postulating the individual level of the political leader as a key variable. This study argues that his personal experience and beliefs and world views formed by his life history, and Bolsonaro's political calculation that would strengthen his domestic political support through linking between his domestic politics and diplomatic lines, ultimately influenced the dependent variable. This study is thought to be meaningful in that it enhanced the theoretical implications of not only the theory of foreign policy determinants but also the understanding of Brazil's foreign policy by explaining the factors of Brazil's pro-U.S. and anti-China diplomacy through focusing on an individual level.

• The Journal of the Acoustical Society of Korea
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• v.42 no.6
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• pp.572-583
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• 2023

Demand for wood in construction is increasing worldwide. In Korea, technical reviews of high-rise Cross Laminated Timber (CLT) buildings are under way. In this paper, Floor Impact Sound Insulation Performance (FISIP) and Transmission Loss (TL) of 150 mm thick CLT floor panels made of two domestic species, Larix kaempferi and Pinus densiflora, are investigated. The CLT slabs were tested in reverberation chambers connected vertically. When comparing Single Number Quantity (SNQ) of FISIP of the bare panels, the Larix CLT is 3 dB lower in heavy-weight and 1 dB in light-weight than the Pinus CLT. However, there was no difference when concrete toppings were added to improve the performance. As the concrete toppings became thicker, the heavy-weight was reduced by 9 dB ~ 20 dB, and the light-weight by 20 dB ~ 30 dB. And the analysis of these results with area density has confirmed that the area densities are highly correlated (R² = 0.94 ~ 0.99) to the FISIP of the CLT. The types of CLT didn't affect the TL. Comparison of theoretical TL values with measured TL values has shown that the frequency characteristics are similar but 8 dB ~ 12 dB lower in measured values. The relationship between the TL and frequency characteristics of the tested CLT slabs was derived by using the correction value.

• Korean Journal of Organic Agriculture
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• v.32 no.1
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• pp.75-90
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• 2024

Biochar is a solid substance with a high carbon content, as it is made out of biomass pyrolyzed under the condition of limited oxygen. This product has attracted attention as an environment-friendly soil amendment because it contributes to carbon neutrally and has improvement effects on the soil environment. This study conducted an experiment to evaluate soil physiochemical properties and microbial community changes in a melon greenhouse according to the applied amount of biochar to investigate the growth characteristics and yields of melons accordingly. In soil physical properties, an increase in the applied amount of biochar resulted in a decrease in bulk density and an increase in porosity of the soil, improving air permeability. In soil chemical properties, an increase in the applied amount of biochar led to a increasing of pH, organic matter and available phosphate content. In the growth characteristics of melons, there was a growing tendency of plant height, leaf length and leaf width according to the increasing application of biochar until 10,000 kg/ha. Moreover, melon yields also increased as the amount of biochar, 13~16% higher in 10,000 kg/ha biochar application than no treatment. Compared differences among microbial communities in the soil according to the application of biochar and found that plant beneficial bacteria dominated in biochar treatments. This study demonstrated the potential of biochar as an effective soil amendment in melon greenhouse by showing improvements in soil physicochemical properties and microbial communities.