• Journal of the Korean Geotechnical Society
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• v.35 no.11
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• pp.37-49
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• 2019

In order to analyze the effect of burial depth on the generation of ground cavities and cave-ins, a series of model experiments with different height of model ground were performed. Digital images of the model ground were captured to evaluate the internal deformation of the model grounds by adopting the PIV (Particle Image Velocimetry) technique. Additionally, the vertical displacement at the surface, the size of the cavity, and the weight of the discharged soil were measured in each test. The results indicate that the model ground with low burial depth, which does not satisfy the criterion, was more vulnerable to ground cavities and cave-ins than the model ground with high burial depth.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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• pp.466-471
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• 2014

The interior vehicle noise due to the exterior aerodynamic field is an important topic in the acoustic design of a car. The air flow detached from the A-pillar and impacting the side windows are of particular interest as they are located close to the driver / passenger and provides a lower insulation index than the trimmed car body parts. This paper presents a numerical analysis method for a simplified vehicle model. The internal air cavity including trim component are included in the simulation. The car body includes the windshield and two side windows. The body is made of aluminum and trimmed with porous layers. The methodology proposed in this paper relies on two steps: the first step involves the computation of the exterior flow and turbulence induced non-linear acoustic field using PowerFlow. The second step consists in the computation of the vibro-acoustic transmission through the window using the finite element vibro-acoustic solver Actran. Additionally in order to validate the numerical process, an experimental set-up has been created based on the simplified vehicle. The vibration of the windshield and windows, the total wind noise level results and the relative contributions of the different windows are then presented and compared to measurements. The influence of the flow yaw angle (different wind orientation) is also assessed.

• Journal of the Korean Geotechnical Society
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• v.20 no.3
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• pp.13-22
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• 2004

In case of the lateral movement accurring at soft ground where a row of piles are installed, the crown failure at external arch zone of soil arching is firstly developed, and the cap failure at wedge zone in front of piles is lastly developed. Therefore, the lateral earth pressure acting on a row of piles due to soil movement should be calculated in each condition of crown and cap failures around piles. A theoretical equation of crown failure can be proposed using a cylindrical cavity expansion theory. The theoretical equation of crown failure is mainly affected by two factors. One is related to soil properties such as internal friction angle, cohesion and horizontal pressure, and the other is related to pile factors such as diameter, installation interval. Meanwhile, the yield range of lateral earth pressure is established in the estimation of theoretical equation based on crown and cap failures around piles. The theoretical values based on crown and cap failures are compared with the experimental values. The experimental values are located in the range proposed by theoretical values. Thus, it is confirmed that the theoretical values proposed in the study are very reasonable.

• The Korea Journal of Herbology
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• v.32 no.1
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• pp.63-68
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• 2017

Objectives : HT042 is a combination of three herbal extracts from the roots of Astragalus membranaceus, the stems of Eleutherococcus senticosus and the roots of Phlomis umbrosa, which has been demonstrated to increase longitudinal bone growth rate. The aim of this study was to assess the safety of HT042 after repeated oral administration. Methods : A 14-day repeated oral dose toxicity study was conducted using male and female Sprague-Dawley rats. HT042 was administered orally at repeated doses of 500, 1,000 and 2,000 mg/kg/day for 14 days. Clinical signs and mortality were observed daily, whereas body weight and food consumption were recorded weekly throughout the experiment. At the end of the study, blood was taken from the posterior vena cava for hematology and serum biochemistry. All organs of the body surface, subcutis, head, thoracic cavity, and abdominal cavity were observed grossly. Then, the internal organs were removed and weighed. Results : No death occurred and no significant changes in clinical sign, body weight, food consumption and serum biochemistry parameters were observed in male and female rats over the study period. Although there were some alterations in hematologic and necropsy findings, and organ weights, these changes were not considered toxicologically significant. Conclusions : These results suggest that the 14-day repeated administration of HT042 does not produce any significant oral toxicity at doses of up to 2,000 mg/kg/day in male and female rats under the present experimental conditions.

• Journal of Ginseng Research
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• v.39 no.4
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• pp.406-413
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• 2015

Background: Pathogenesis-related 10 (PR-10) proteins are small, cytosolic proteins with a similar three-dimensional structure. Crystal structures for several PR-10 homologs have similar overall folding patterns, with an unusually large internal cavity that is a binding site for biologically important molecules. Although structural information on PR-10 proteins is substantial, understanding of their biological function remains limited. Here, we showed that one of the PgPR-10 homologs, PgPR-10.3, shares binding properties with flavonoids, kinetin, emodin, deoxycholic acid, and ginsenoside Re (1 of the steroid glycosides). Methods: Gene expression patterns of PgPR-10.3 were analyzed by quantitative real-time PCR. The three-dimensional structure of PgPR-10 proteins was visualized by homology modeling, and docking to retrieve biologically active molecules was performed using AutoDock4 program. Results: Transcript levels of PgPR-10.3 expressed in leaves, stems, and roots of 3-wk-old ginseng plantlets were on average 86-fold lower than those of PgPR-10.2. In mature 2-yr-old ginseng plants, the mRNA of PgPR-10.3 is restricted to leaves. Ginsenoside Re production is especially prominent in leaves of Panax ginseng Meyer, and the binding property of PgPR-10.3 with ginsenoside Re suggests that this protein has an important role in the control of secondary metabolism. Conclusion: Although ginseng PR-10.3 gene is expressed in all organs of 3-wk-old plantlets, its expression is restricted to leaves in mature 2-yr-old ginseng plants. The putative binding property of PgPR-10.3 with Re is intriguing. Further verification of binding affinity with other biologically important molecules in the large hydrophobic cavity of PgPR-10.3 may provide an insight into the biological features of PR-10 proteins.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.291-291
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• 2013

The interior vehicle noise due to the exterior aerodynamic field is an important topic in the acoustic design of a car. The air flow detached from the A-pillar and impacting the side windows are of particular interest as they are located close to the driver / passenger and provides a lower insulation index than the trimmed car body parts. HMC is interested in the numerical prediction of this aerodynamic noise generated by the car windows with the final objective of improving the products design and reducing this noise. The methodology proposed in this paper relies on two steps: the first step involves the computation of the exterior flow and turbulence induced non-linear acoustic field using the CAA(Computational aeroacoustics) solver CAA++. The second step consists in the computation of the vibro-acoustic transmission through the side window using the finite element vibro-acoustic solver Actran. The internal air cavity including trim component are included in the simulation. In order to validate the numerical process, an experimental set-up has been created based on a generic car shape. The car body includes the windshield and two side windows. The body is made of aluminum and trimmed with porous layers. First, this paper describes the method including the CAA and the vibro-acoustic models, from the boundary conditions to the different components involved, like the windows, the trims and the car cavity is detailed. In a second step, the experimental set-up is described. In the last part, the vibration of the windshield and windows, the total wind noise level results and the relative contributions of the different windows are then presented and compared to measurements. The influence of the flow yaw angle (different wind orientation) is also assessed.

• Journal of the Korean Chemical Society
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• v.36 no.4
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• pp.523-535
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• 1992

The conformations of hexapeptides, their complexation with alkali cations and the inhibition of the cation transport by 5,5-diphenylhydantoin(DPH) were studied theoretically using ECEPP/2 and MM2 force field. Several low energy conformations of uncomplexed cyclic hexapepides are obtained, and they adopt compact conformations in which most amide hydrogens form intramolecular hydrogen bond to amide carbonyl oxygens. The complexation energy of the peptide with $Na^+$ ion and DPH is -60 kcaal/mol and -18 kcal/mol, respectively. However, no suitable cavity to bind metal cation exists for the local minima of the peptide, and the internal energy of the uncomplexed hexapeptide having cavity is higher than that of the uncomplexed global minimum of this work by 10 kcal/mol. Also, one of the most important amino acid residue to bind DPH is Glycine, and this can explain experimental observation that the replacement of Gly by Sarcosine (N-methyl Glycine) reduce the inhibition ability of the cation transport.

• Journal of Veterinary Clinics
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• v.36 no.3
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• pp.133-138
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• 2019

The present study was performed to identify the nematodes recovered from the Eurasian jay, Garrulus glandarius brandtii, from Daejeon Metropolitan City, the Republic of Korea. Total five nematode worms were detected in the body cavities of two out of the twenty birds necropsied, and they were identified using morphological features, light and scanning electron microscope (SEM), and molecular (18S rRNA analysis) methods. The nematodes were all female Diplotriaena manipoli and had numerous eggs at different developmental stages in the uterus. The nematodes were long and slender measuring about 123-145 mm. The eight submedian cephalic papillae were arranged into four large, outer papillae and four small, inner-circle papillae. A pair of amphidal pores were located at the lateral portion of the mouth. The manubrium apex of trident was rounded and three branches of trident were bluntly rounded at the posterior ends. Using 18S rRNA partial sequence arrangements, DNA analysis of nematode worms was also carried out, and they were identified to be close to the Serratospiculum tendo based on a phylogenic tree analysis. To our knowledge, this is the first report on the molecular characterization and SEM study of D. manipoli.

• Economic and Environmental Geology
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• v.50 no.6
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• pp.487-495
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• 2017

A granite rock body, called 'Bukbawi', located on a mountaineering trail at Mt. Palgong Provincial Park is popular among the public because it resembles a percussion instrument. If someone hits the specific surface area of this rock body, people can hear drum-like sound. Such phenomenon may be geologically associated with exfoliation process of the granite body or miarolitic cavity developed after gasses escaped during formation of granite. To understand better the inner structure causing drum-like sound, we carried out a non-destructive ground-penetrating radar survey. In this study, as our primary target is very close to the surface, we utilized 1 GHz antennas to produce high-resolution near-surface images. In order to construct 3-D internal images, the measurements were conducted along a pre-defined grid. The processed radargrams revealed that the locations associated with 'drum' sound coincide with strong reflections. In addition, both reflection patterns of fracture and cavity were observed. To further quantify the observed reflections, we simulated GPR scans from a synthetic fracture in a granite body, filled with different materials. The simulated results suggest that both exfoliation process and miarolitic cavity may have contributed to the 'drum' phenomena. Furthermore, the radargrams showed a well-developed cavity signature where two major reflection planes were crossed. Thus, our study is an example of non-destructive geophysical studies that can promote Earth Science in the broader community by examining geological structures attracting the public.

• Tuberculosis and Respiratory Diseases
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• v.62 no.5
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• pp.374-381
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• 2007

Background: This study evaluated which CT findings could be used to predict the negative results of a sputum smear in patients with active pulmonary tuberculosis and multiple cavities. Methods: Thirty-eight patients with active pulmonary tuberculosis and multiple cavities on CT were classified into 2 groups: smear-positive (n = 30) and -negative (n = 8). The CT findings were reviewed retrospectively. The maximum internal diameter of the largest cavity, the number of the cavities and lobes with cavities, and the characteristics of the associated findings such as consolidation, ground glass opacity, micronodules and nodule were accessed. The number of cavities above 20 mm in the maximum internal diameter and a necrotizing pneumonia-like pattern were also evaluated. Result: The maximum internal diameter and number of cavities was $32.23{\pm}17.66mm$ and $15.50{\pm}11.12mm$ (p = 0.0042), and $5.53{\pm}3.17$ and $2.43{\pm}1.13$ (p = 0.0002) in the smear-positive and -negative group, respectively. Three or more cavities were observed at 76.7% and 12.5% in the smear-positive and -negative group, respectively (p < 0.005). There were $2.00{\pm}1.34$ and $0.25{\pm}0.46$ (p = 0.001), and $1.5{\pm}1.50$ and $0.38{\pm}0.52$ (p =0.0016) lobes with consolidation and ground glass opacity in the smear-positive and -negative group, respectively. A necrotizing pneumonia-like pattern was observed in 43.3% of the smear-positive group only. The other findings were similar in both two groups. The sensitivity, specificity, positive and negative predictive value for the presence of at least a finding of consolidation, more than 3 cavities or the largest cavity > 20 mm in the maximum internal diameter were 100%, 62.5%, 90.9%, and 100%, respectively. Conclusion: Two cavities 20 mm or less in the maximum internal diameter without consolidation on CT might be associated with a negative result of the sputum smear in patients with active pulmonary tuberculosis and multiple cavities.