• Fire Science and Engineering
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• v.21 no.1 s.65
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• pp.74-81
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• 2007

In this study, we have evaluated the hazardous factors of fires such as heat release rate, smoke density, ignition temperature, and flammability of carpet and curtain used in the public facilities. As a result of flame retardant treatment, the heat release rate of materials treated with flame retardant was lower than that of not treated. However, the smoke density of treated materials was higher than that of not treated. Also, we have investigated the fire characteristics of used and unused carpet. As a result, the heat release rate and the smoke density of used for 3 years carpet were higher than those of unused carpet. The distinct differences of flammability and ignition temperature between used and unused carpet were confirmed.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.53.1-53.1
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• 2011

We analyze the halo and galaxy catalogs from the Millennium simulations at redshifts z=0, 0.5, 1 to determine the alignment profiles of cluster galaxies in terms of the matter density correlation coefficient and discuss a cosmological implication our result has for breaking parameter degeneracies. For each selected cluster, we measure the alignment between the major axes of the pseudo inertia tensors from all satellites within cluster's virial radius and from only those satellites within some smaller radius. Then we average the measured values over the similar-mass sample to determine the cluster galaxy alignment profile as a function of top-hat scale difference at each redshift. It is shown that the alignment profile of cluster galaxies is well approximated by a power-law of the nonlinear density correlation coefficient that is independent of the power spectrum normalization and bias factor. The alignment profile of cluster galaxies is found to have higher amplitude and lower power-law index when averaged over the larger-mass sample and to have rather weak redshift-dependence. This result is consistent with the picture that the satellite galaxies retain the memory of the external tidal fields right after merging and infalling into the clusters but they gradually lose the initial alignment tendency as the cluster's relaxation proceeds. Demonstrating that the nonlinear density correlation coefficient varies sensitively with the density parameter and neutrino mass fraction, we discuss a potential power of the cluster galaxy alignment profile as an independent probe of cosmology.

• The Journal of Korean Academy of Prosthodontics
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• v.24 no.1
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• pp.91-103
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• 1986

Using imprint cultures and epithelial smears, the density and prevalence of colonization of oral mucosal sites and denture surfaces by Candida albicans has been determined in 28 healthy dentate subjects and 20 denture wearers. With questionnaire, oral and denture examination, the relationship between the carrier rates and several factors; DMFT, oral hygiene index, salivary pH & denture plaque score were studied. But these factors have not significant relationship to the carrier rates. Imprint culture appears to be sensitive technique for detecting candidal carriers and be useful for distinguishing between the healthy carrier state and candidal infection. Cigarette smokers had a significantly increased carrier state (P<0.05) compared with nonsmoker in male dentate subjects. Female were more frequent carriers than male in dentate and denture group, but these differences were not significant. In denture wearers, there was a higher density and frequency of candidal colonization of all mucosal sites sampled, compared with that of healthy dentate group especially anterior palate and posterior palate showed highly significant differences in frequency of candidal colonization (P<0.05). The distribution of Candida albicans is not uniform throughout the mouth. The tongue in the healthy dentate subjects and the impression surfaces of upper dentures are the primary oral reservoirs for the fungus. Overnight wearing of dentures was associated with increased density and frequency of candidal colonization and density.

• Magazine of the Korean Society of Agricultural Engineers
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• v.36 no.3
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• pp.74-83
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• 1994

A series of isotropic consolidation tests, undrained and drained triaxial compression tests was carried out to investigate the physical characteristics and behaviours of marine silty sands collected from the western coast of Korea. This study also included a theoretical development of the constitutive equation to evaluate stress-strain relationship and volume change of silty sands. The results and main conclusions of the study are summarized as follows; 1. Isotropic compression and swelling index are linearly decreased with an increase in relative density. 2. Both undrained shear strengh and elastic modulus are increased with an increase in relative density and confining pressure. 3. Internal friction angles obtained from drained and undrained compression tests of the soils are proportional to relative density. 4. The phenomenon of dilatancy of each sample is less profound when confining stress is increased but more profound when relative density is increased. 5. The slope of critical state lines is 1.78 for Saemangum, 1.70 for Siewha and 1.26 for Sukmoon sands. 6. In this study, Drucker-Praper type criterion is used and hardening function of Cap model is modified by hyperbolic fuction. This will improve a lack of physical meaning of hardening parameters in conventional Cap model. 7. A newly developed constitutive equation to the forementioned silty sands and checked its applicability. This is in good agreement with the measured data.

• Journal of Forest and Environmental Science
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• v.26 no.2
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• pp.117-129
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• 2010

The present study was undertaken in moist temperate forest of Mandal-Chopta area in the Garhwal region of Uttarakhand, India. The aim of the present study was to assess the physical properties of soils in relation to the forest structure and composition. Twelve forest types according to the altitude, slope aspect and species compositions were selected for the study. Physical properties of soil i.e., soil colour, soil texture (per cent of sand, silt and clay), moisture content, water holding capacity, porosity, bulk density (gm/$cm^3$) and void ratio were analyzed for three different depths viz., (i) 'upper' (0-10 cm), (ii) 'middle' (11-30 cm) and (iii) 'lower' (31-60 cm) in all the selected forest types. Phytosociological and diversity parameters viz. total basal cover ($Gha^{-1}$), stem density ($Nha^{-1}$), tree species richness, Simpson concentration of dominance and Shannon-Wiener diversity index were also calculated for each forest type. This study also provides the comparisons between the results of physical analysis of the present study with numerous other previous studies in the temperate Himalayan region of the Uttarakhand.

• East Asian Economic Review
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• v.27 no.1
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• pp.33-60
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• 2023

This paper analyzes the entire distribution of stock market returns/volatility in five emerging markets (ASEAN5) and figures out the conditional distribution of the CHI_EPU index. The aim is to examine the impact of CHI_EPU on the stock returns/volatility density of ASEAN5 markets. It also examined whether changes in CHI_EPU explain returns at higher or lower points (abnormal returns). This paper models the behaviour of stock returns from March 2011 to June 2018 using a non-parametric conditional density estimation approach. The results indicate that CHI_EPU diminishes stock returns and augments volatility in ASEAN5 markets, except for Malaysia, where it affects stock returns positively. The possible reason for this positive impact is that EPU is not the leading factor reducing Malaysian stock returns; but, other forces, such as dependency on other countries' stock markets and global factors, may have a positive impact on stock returns (Bachmann and Bayer, 2013). Thus, the risk of simultaneous investment in Chinese and ASEAN5 stock markets, except Malaysia, is high. Further, the degree of this influence intensifies at extreme high/low intervals (positive/negative tails). The findings of this study have significant implications for investors, policymakers, market agents, and analysts of ASEAN5.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.36-36
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• 2020

Symplocos Jacq. including about 350 species is the sole isolated genus of the family Symplocaceae. Despite poorly documented species delimitation and unresolved taxonomic nomenclature four species of Symplocos (S. coreana, S purnifolia, S sawafutagi, and S. tanakana) have been described in Korea. In this study, we carried the comparative wood anatomy of all the four species of Korean Symplocos to understand the wood anatomical variations within these four species. The result of this study indicated that Korean Symplocos are comparatively indistinguishable in terms of their qualitative wood features except for exclusively uniseriate rays present in S. purnifolia instead of uni- to- multiseriate in other three species. However, discrepancies are observed in quantitative wood variables such as vessel density, vessel size, and ray density. The vessel density of S. purnifolia (highest among the four species) is more than two times higher than the S. sawafutagi (lowest among the four species) and S. tanakana. On the other hand, vessel size is likewise reverse to the vessel number relationships i. e. vessel circumference and diameter in both planes of S. sawafutagi and S. tanakana is almost twice a larger than S. purnifolia. Interestingly, S. coreana remains in between of these two groups in terms of vessel features and closer to S. purnifolia in terms of ray density. The cluster analysis based on the paired group (UPGMA) algorithm using the Euclidean similarity index clearly differentiates S. purnifolia from the rest of the taxa representing the first isolated clade of the tree.

• Journal of Korean Society for Quality Management
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• v.30 no.3
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• pp.66-78
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• 2002

Process capability indices are being used as indicators for measurements of process capability for SPC of quality assurance system in industries. In view of the enhancement of customer satisfaction, process capability indices in which loss functions are used to deal with the economic loss In the processes deviated from the target, are in an adequate representation of the customer's perception of quality In this connection, the loss function has become increasingly important in quality assurance. Taguchi uses a modified form of the quadratic loss function to demonstrate the need to consider the proximity to the target while assessing its quality. But this traditional quadratic loss function is inadequate to assessing the quality and quality improvement since different processes have different sets of economic consequences on the manufacturing, Thereby, a flexible approach to the development of the loss function needs to be desired. In this paper, we introduce an easily understood loss function, based on reflection of probability density function of the normal distribution. That is, the Reflected Normal Loss function can be adapted to an asymmetric loss as well as to a symmetric loss around the target. We propose that, instead of the process variation, a new capability index, CpI using the Reflected Normal Loss Function that can accurately reflect the losses associated with the process and a new capability index CpI Is compared with the classical indices as $C_{p}$ , $C_{pk}$, $C_{pm}$ and $C_{pm}$ $^{+}$.>.+/./.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.81-84
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• 2004

Plant-parasitic nematodes were surveyed at peach orchards in Gyeongbuk province for three years from 2000 to 2002. Species, density, frequency, Simpson's index, Shannon and Wiener index, and prominence value were analyzed. Plant-parasitic nematodes were isolated from 97 orchards out of 124 orchards. More important plant-parasitic nematode genera on peach were Tylenchorhynchus nudus, Criconemoides informis, Paratylenchus elachistus, Pratylenchus vulnus, and Helicotylenchus digonichus. Aphelenchus sp., Tylenchus sp., Heterodera sp., Scutellonema sp. were found, but were not important. Root-knot nematodes were not found even though they were serious in foreign countried.

• Imaging Science in Dentistry
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• v.47 no.2
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• pp.87-92
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• 2017

Purpose: The aim of this study was to determine whether the panoramic mandibular index (PMI) is useful for assessing bone mineral density. We also analyzed the potential correlations between PMI parameters and patient age. Materials and Methods: Four observers measured the PMI of both sides of the mental foramen using a picture archiving and communication system and images in the Digital Imaging and Communications in Medicine format. They studied 300 panoramic radiographic images of patients belonging to the following age groups: 40-49 years, 50-59 years, 60-69 years, 70-79 years, and 80-89 years. The observers were allowed to zoom in or out and to adjust the contrast of the images. Further, they were instructed to record the reasons for any measurements that could not be made. Then, we conducted a reliability analysis of the measured PMI and assessed the correlations between different patient age groups and the 3 parameters used for determining the PMI from the available data. Results: Among the 600 data items collected, 23 items were considered unmeasurable by at least 1 observer for the following 4 reasons: postoperative state, lesion, unidentified mental foramen, and alveolar bone loss. The intraobserver reproducibility of the measurable data was 0.611-0.752. The mandibular cortical width (MCW) decreased significantly as patient age increased. Conclusion: PMI had limited usability when the margin of the mental foramen was not clear. In contrast, MCW, a parameter used for determining the PMI, had fewer drawbacks than the PMI with respect to bone mineral density measurements and exhibited a significant correlation with patient age.