• International conference on construction engineering and project management
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• 2017.10a
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• pp.89-98
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• 2017

The floor heating method generally uses a wet construction method including the installation of resilient material, lightweight foam concrete, heating piping, and finishing mortar. Such a wet construction method not only delays other internal finishing processes during curing period for two mortar pouring process, but also has a disadvantage that it is difficult to replace the floor heating layer when it deteriorated because it is integrated with the frame. Dry floor heating construction method can be a good alternative in that it can solve these defects. Conversely, when it applied to the wall structure that is vulnerable to the interlayer noise compared with the column-beam structure, the question about the heavy-impact sound(HIS) insulation performance is raised. Therefore, conventional dry floor heating method is hard to apply to the wall structure apartments. Therefore, for the purpose to improve the applicability of dry floor heating method in wall structure apartments, this study investigated the change of floor impact sound, especially HIS insulation performance which is one of the required performance for the floor structure. This study tried to examine whether the change of heavy-impact sound pressure level(SPL) shows a tendency at the significant level according to the shape and mass of the floor structure. Through filed experiments on wall structure apartment, this study confirmed that the form of the raised floor shows better HIS insulation performance than the fully-supported form. In addition, it was also confirmed that the HIS insulation performance increases with the mass on the upper part. Moreover, this study found the fact that a mass of about 30 kg/m² or more should be placed on the upper structure to reduce the heavy-impact SPL according to the bang machine measuring method. Although this study has a limit due to insufficient experiment samples, if the accuracy of this study is increased, it will contribute to the diffusion of dry floor heating by setting the HIS insulation performance target and designing the dry floor heating structure that meets the target.

• Journal of The Geomorphological Association of Korea
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• v.18 no.3
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• pp.1-10
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• 2011

Sanbangsan and Yongmuri Beach as geosites are very wide areas, and tourists have accessed them via various courses; hence the need to double the number of geosite signs and disperse them at each point. The signs should read "Sanbangsan lava dome," "Yongmuri tuff ring," and "Relationship between the Sanbangsan lava dome and Yongmuri tuff ring." The contents of the sign should be systemic, simple, and clear because tourists have to read it in a short time. The viewpoint of the research area can be largely divided into Sanbangsan View, Yongmuri Beach View, Sanbangsan, and Yongmuri Beach View. Three of each viewpoint (total of 9 viewpoints) can be placed. In the geosite of Sanbangsan and Yongmuri Beach are 5 sub-theme views including the boundary sheet of Sanbangsan and Yongmuri tuff ring, xenolith basalt, marine pothole, tafoni, and crossed sedimentary layer. These sub-theme views are important in understating not only the geosite but the overall geopark as well, so they should be developed and utilized aggressively.

• Restorative Dentistry and Endodontics
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• v.47 no.4
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• pp.36.1-36.17
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• 2022

Objectives: This study aimed to evaluate the effect of aging on the marginal quality of glass hybrid (GH) material used to elevate dentin gingival margins, and to analyze the consistency of the results obtained by 3 in vitro methods. Materials and Methods: Ten teeth received compound class II cavities with subgingival margins. The dentin gingival margins were elevated with GH, followed by resin composite. The GH/gingival dentin interfaces were examined through digital microscopy, scanning electron microscopy (SEM) using resin replicas, and according to the World Dental Federation (FDI) criteria. After initial evaluations, all teeth were subjected to 10,000 thermal cycles, followed by repeating the same marginal evaluations and energy dispersive spectroscopy (EDS) analysis for the interfacial zone of 2 specimens. Marginal quality was expressed as the percentage of continuous margin at ×200 for microscopic techniques and as the frequency of each score for FDI ranking. Data were analyzed using the paired sample t-test, Wilcoxon signed-rank test, and Pearson and Spearmen correlation coefficients. Results: None of the testing techniques proved the significance of the aging factor. Moderate and strong significant correlations were found between the testing techniques. The EDS results suggested the presence of an ion-exchange layer along the GH/gingival dentin interface of aged specimens. Conclusions: The marginal quality of the GH/dentin gingival interface defied aging by thermocycling. The replica SEM and FDI ranking results had stronger correlations with each other than either showed with the digital microscopy results.

• Wind and Structures
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• v.37 no.6
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• pp.413-423
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• 2023

Wind turbines are usually steel hollow structures that can be vulnerable to dramatic failures due to high-intensity wind (HIW) events, which are classified as a category of localized windstorms that includes tornadoes and downbursts. Analyzing Wind Turbines (WT) under tornadoes is a challenging-to-achieve task because tornadoes are much more complicated wind fields compared with the synoptic boundary layer wind fields, considering that the tornado's 3-D velocity components vary largely in space. As a result, the supporting tower of the wind turbine and the blades will experience different velocities depending on the location of the event. Wind farms also extend over a large area so that the probability of a localized windstorm event impacting one or more towers is relatively high. Therefore, the built-in-house numerical code "HIW-WT" has been developed to predict the straining actions on the blades considering the variability of the tornado's location and the blades' pitch angle. The developed HIWWT numerical model incorporates different wind fields that were generated from developed CFD models. The developed numerical model was applied on an actual wind turbine under three different tornadoes that have different tornadic structure. It is found that F2 tornado wind fields present significant hazard for the wind turbine blades and have to be taken into account if the hazardous impact of this type of unexpected load is to be avoided.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.4
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• pp.116-129
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• 2023

Recently, interest in autonomous driving has drawn attention to autonomous cooperative driving, which considers the development of driving technology of autonomous vehicles and the development of infrastructure that constitutes a driving environment. According to the concept of autonomous cooperative driving, This study analyzes the new infrastructure for autonomous driving that can complement the information of existing precise road maps and adding HD map layer as the new infrastructure. The new infrastructure for autonomous driving presented two types of improved facilities and one type of sensor only facility. Analysis of HD maps shows that information such as junction points rarely changes, but it is expected that infrastructure for autonomous driving can be added to convey the meaning of paying attention to obstacles that may arise at the junction. In this way, the new infrastructure for autonomous driving needs to support the roles of guidance, instruction, and attention that existing road facilities.

• Corrosion Science and Technology
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• v.22 no.6
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• pp.419-428
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• 2023

Seawater has been used to cool devices in nuclear power plants. However, the pipes used to transport seawater are vulnerable to corrosion; hence, the inner side of pipelines is coated with an epoxy layer as prevention. Upon coating damage, the pipe becomes exposed, and corrosion progresses. The major cause is widely known as cavitation corrosion, causing the degradation of mechanical properties. In this study, corroded specimens were prepared using cavitation and immersion methods to clarify the degradation trend of mechanical properties with corrosion. Three different types of epoxy coatings were used, and accelerated cavitation procedures were composed of amplitudes of 15 ㎛, 50 ㎛, and 85 ㎛ for 2 h, 4 h, and 6 h. The immersion periods were 3 and 6 weeks. We conducted instrumented indentation tests on all degradation samples to measure mechanical properties. The results showed that higher cavitation amplitudes and longer cavitation or immersion times led to more degradation in the samples, which, in turn, decreased the yield strength. Of the three samples, the C coating had the highest resistance to cavitation and immersion degradation.

• Journal of Veterinary Clinics
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• v.41 no.1
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• pp.49-53
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• 2024

A two-year-old, spayed female, 22.5 kg Pungsan was referred with chronic crusts and erosion on the nose. A referring veterinarian prescribed an anti-inflammatory dose (0.5-1 mg/kg/day) of oral glucocorticoids for 5 months, but skin lesions showed no meaningful improvement. A dermatological evaluation revealed a crust, depigmentation, erosion, and erythematous lesion over the nasal planum with a loss of the normal cobblestone texture. Also, firm and multifocal plaques over the thigh, groin, axilla, and dorsum were detected. A cytology examination on the nose, thigh, groin, axilla, and dorsum revealed moderate neutrophilic inflammation and bacterial infection. Abdominal radiography and ultrasonography revealed subcutaneous calcified materials along the thigh, groin, axilla, and dorsum. Calcinosis cutis was suspected because of the adverse effect of previous prolonged corticosteroid therapy. A histopathology examination of the nose lesion revealed moderate to severe degenerative or apoptotic changes of the basal layer and lymphoplasmacytic interface dermatitis. Facial discoid lupus erythematosus (FDLE) was diagnosed based on the history and the clinical, cytological, and histopathological results. Minocycline (7 mg/kg PO q 12 h) and niacinamide (500 mg/dog PO q 12 h) were prescribed as initial treatment. Glucocorticoids were not administered due to the presence of calcinosis cutis induced by previous corticosteroid treatment. After 6 weeks of treatment, the clinical signs on the nose were mildly improved. At this time, topical 1% pimecrolimus cream (twice daily) was initiated, while minocycline and niacinamide were continued at the same dose. The nasal planum markedly improved after 6 weeks of additional treatment, hence minocycline and niacinamide were prescribed for an additional 2 weeks and stopped, and the patient was continued solely on topical pimecrolimus. The dog's skin lesion has been maintained in clinical remission with topical 1% pimecrolimus twice daily for more than 5 months.

• Korean Journal of Head & Neck Oncology
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• v.40 no.1
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• pp.33-36
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• 2024

Pleomorphic adenoma (PA) is a commonly occurring benign tumor originating in the salivary glands. The incidence is mostly in the parotid glands (85%) followed by minor salivary glands (10%). Pleomorphic adenoma from minor salivary glands of the lips is a rare neoplasm. Here, we present a case of a patient with PA in the upper lip, reporting a common neoplasm in a rare site. A 82-year-old male with a slowly progressing swelling that occurred 20years ago on the upper white lip. This tumor is not associated with pain and tenderness. The mass was about 1.5x1.5cm sized, circumscribed, sessile and firm on the external upper lip without oral side bulging (Fig. 1). The tumor was removed completely with a elliptical incision under local anesthesia. The encapsulated mass was measured 0.9x0.9x0.6cm. On histology, a well-circumscribed growth was seen comprising epithelial and stromal components. The epithelial component formed glandular structures lined by round-to oval cells having small nuclei, pink cytoplasm and myoepithelial basal cell layer while the stroma had a fibromyxoid appearance(Fig. 2). Postoperatively wound was well healed without recurrence after 6months. Pleomorphic adenoma of the upper lip is a rare neoplasm, especially not intraoral growth. For aesthetic good result, the mass was removed without hesitation. It is required a high index of suspicion and a long-term follow-up because it could recur and rarely be transformed into malignancy.

• Journal of Dental Anesthesia and Pain Medicine
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• v.24 no.1
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• pp.67-73
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• 2024

Background: Nitrous oxide has been an integral part of surgical anesthesia for many years in the developed world and is still used in developing countries such as India. The other main concerns in low-resource countries are the lack of an advanced anesthesia gas-scavenging system and modular surgical theatres. As a greenhouse gas that has been present in the atmosphere for more than 100 years and damages the ozone layer, nitrous oxide is three times worse than sevoflurane. Here, we conducted an observational study to quantify the annual nitrous oxide consumption and its environmental impact in terms of carbon dioxide equivalence in one of busiest tertiary health care and research centers in Northern India. Methods: Data related to nitrous oxide expenditure' from the operation theatre and manifold complex of our tertiary care hospital and research center from 2018 to 2021 were collected monthly and analyzed. The outcomes were extracted from our observational study, which was approved by our institutional ethics board (INT/IEC/2017/1372 Dated 25.11.2017) and registered prospectively under the Central Registry (CTRI/2018/07/014745 Dated 05.07.2018). Results: The annual nitrous oxide consumption in our tertiary care hospital was 22,081.00, 22,904.00, 17,456.00, and 18,392.00 m³ (cubic meters) in 2018, 2019, 2020, and 2021, respectively. This indicates that the environmental impact of nitrous oxide (in terms of CO₂ equivalents) from our hospital in 2018, 2019, 2020, and 2021 was 13,016.64, 13,287.82, 10,289.94, and 10,841.24 tons, respectively. Conclusion: This huge amount of nitrous oxide splurge is no longer a matter of laughter, and serious efforts should be made at every central and peripheral health center level to reduce it.

• Advances in materials Research
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• v.13 no.3
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• pp.153-160
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• 2024

This study investigates the application of alternating current (AC) and direct current (DC) anodization techniques on stainless steel 304L (SS304L) in an ethylene glycol and ammonium fluoride (NH4F) electrolyte solution to produce a nano-porous oxide layer. With limited research on AC anodizing of stainless steel, this study focuses on comparing AC and DC anodization in terms of current density versus time response, phase analysis using X-ray diffraction (XRD), and corrosion rate determined by linear polarization. Both AC and DC anodization were performed for 60 minutes at 50 V in an electrolyte solution containing 0.5% NH4F and 3% H₂O in ethylene glycol. The results show that AC anodization exhibited higher current density compared to DC anodization. XRD analysis revealed the presence of ferrite (α-Fe) and austenite (γ-Fe) phases in the as-received specimen, while both AC and DC anodized specimens exhibited only the γ-Fe phase. The corrosion rate of the AC-anodized specimen was measured at 0.00083 mm/year, lower than the corrosion rate of the DC-anodized specimen at 0.00197 mm/year. These findings indicate that AC anodization on stainless steel offers advantages in terms of higher current density, phase transformation, and lower corrosion rate compared to DC anodization. These results highlight the need for further investigation and exploration of AC anodization as a promising technique for enhancing the electrochemical properties of stainless steel.