• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.3017-3029
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• 2023

In the late in-vessel phase of a nuclear reactor severe accident, the internal heat transfer and crust evolution during the debris bed melting process have important effects on the thermal load distribution along the vessel wall, and further affect the reactor pressure vessel (RPV) failure mode and the state of melt during leakage. This study coupled the phase change model and large eddy simulation to investigate the variations of the temperature, melt liquid fraction, crust and heat flux distributions during the debris bed melting process in the hypothetical severe accident of HPR1000. The results indicated that the heat flow towards the vessel wall and upper surface were similar at the beginning stage of debris melting, but the upward heat flow increased significantly as the development of the molten pool. The maximum heat flux towards the vessel wall reached 0.4 MW/m². The thickness of lower crust decreased as the debris melting. It was much thicker at the bottom region with the azimuthal angle below 20° and decreased rapidly at the azimuthal angle around 20-50°. The maximum and minimum thicknesses were 2 and 90 mm, respectively. By contrast, the distribution of upper crust was uniform and reached stable state much earlier than the lower crust, with the thickness of about 10 mm. Moreover, the sensitivity analysis of initial condition indicated that as the decrease of time interval from reactor scram to debris bed dried-out, the maximum debris temperature and melt fraction became larger, the lower crust thickness became thinner, but the upper crust had no significant change. The sensitivity analysis of in-vessel retention (IVR) strategies indicated that the passive and active external reactor vessel cooling (ERVC) had little effect on the internal heat transfer and crust evolution. In the case not considering the internal reactor vessel cooling (IRVC), the upper crust was not obvious.

• Journal of Korea Trade
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• v.27 no.3
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• pp.103-118
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• 2023

Purpose - This study aims to examine the dynamic relationship between the variables impacted by the Regional Comprehensive Economic Partnership (RCEP) and the level of intra-industry trade among member states, with the ultimate objective of deducing the short- and long-term effects of RCEP on trade. Design/methodology - This study focuses on tariffs, GDP growth rates, and the proportion of regional FDI to total FDI as research variables, and employs a panel vector autoregression model and GMM-style estimator to investigate the dynamic relationship between RCEP and intra-industry trade among member countries. Findings - The study finds that the level of intra-industry trade between member states is positively impacted by both tariffs and intra-regional FDI. The impulse response graph shows that tariffs and FDI within the region can promote intra-industry trade among member countries, with a quick response. However, the contribution rates of tariffs and intra-regional FDI are not particularly high at approximately 1.5% and 1.4%, respectively. In contrast, the contribution rate of GDP growth can reach around 8.5%. This implies that the influence of economic growth rate on intra-regional trade in industries is not only long-term but also more powerful than that of tariffs and intra-regional FDI. Originality/value - The originality of this study lies in providing a new approach to investigating the potential impact of RCEP while avoiding the limitations associated with the GTAP model. Additionally, this study addresses existing gaps within the research, further contributing to the research merit of the study.

• Journal of Veterinary Clinics
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• v.40 no.4
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• pp.283-287
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• 2023

A 10-year-old spayed female beagle dog presented with a 2-month history of third-eyelid elevation in the left eye (OS). Ophthalmic examination revealed slightly diminished corneal and palpebral reflexes along with exophthalmos in the OS. Schirmer's tear test and intraocular pressure values were within the normal range for the OS. Slit-lamp biomicroscopy revealed protrusion of the third eyelid and corneal opacity in the OS. Fundoscopy revealed a prominent black mass in the OS covering the optic nerve. Tapetal hyper-reflectivity was also observed around the mass. Ocular ultrasonography showed a 0.74 × 0.67 cm echogenic posterior segment mass around the optic nerve protruding into the retrobulbar space. Computed tomography revealed a contrast-enhanced soft tissue lesion in the posteromedial aspect of the left eyeball protruding into the retrobulbar region, and the optic nerve was suspected to be involved. No evidence of osteolytic changes in the adjacent bone or distant metastasis was observed. Enucleation was performed to prevent potential metastasis or local invasion of the mass and to relieve discomfort due to exposure to keratopathy resulting from lagophthalmos. Histopathological examination revealed a central choroidal melanocytoma extending into the optic nerve. No local recurrence was detected until 16 months postoperatively.

• Coupled systems mechanics
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• v.11 no.5
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• pp.439-458
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• 2022

Over-coating is one of the most popular engineering practices to strengthen Reinforced Concrete (RC) structures, due to the relative quickness and ease of construction. It consists of an external coat bonded to the outer surface of the structural RC element, either by the use of chemical adhesives, mechanical anchor bolts or simply mortar injection. In contrast to these constructive advantages, the numerical estimation of the bearing capacity of the strengthened reinforced concrete element is still complicated, not only for the complexity of modelling a flexible membrane or plate attached to a quasi-rigid solid, but also for the difficulties that raise of simulating any potential delamination between both materials. For these reasons, the standard engineering calculations used in the practice remain very approximated and clumsy. In this work, we propose the formulation of a new 2D solid-layer finite element capable to link a solid body with a flexible thin layer, as it were the "skin" of the body, allowing the potential delamination between both materials. In numerical terms, this "skin" element is intended to work as a transitional region between a solid body (modelled with a classical formulation of a standard quadrilateral four-nodes element) and a flexible coat layer (modelled with cubic beam element), dealing with the incompatibility of Degrees-Of-Freedom between them (two DOF for the solid and three DOF for the beam). The aim of the solid-layer element is to simplify the mesh construction of the strengthened RC element being aware of two aspects: a) to prevent the inappropriate use of very small solid elements to simulate the coat; b) to improve the numerical estimation of the real bearing capacity of the strengthened element when the coat is attached or detached from the solid body.

• Journal of Animal Science and Technology
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• v.65 no.3
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• pp.588-595
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• 2023

The aim of this study was to investigate the effects of heat stress on milk traits in South Korea using comprehensive data (dairy production and climate). The dataset for this study comprised 1,498,232 test-day records for milk yield, fat- and protein-corrected milk, fat yield, protein yield, milk urea nitrogen (MUN), and somatic cell score (SCS) from 215,276 Holstein cows (primiparous: n = 122,087; multiparous: n = 93,189) in 2,419 South Korean dairy herds. Data were collected from July 2017 to April 2020 through the Dairy Cattle Improvement Program, and merged with meteorological data from 600 automatic weather stations through the Korea Meteorological Administration. The segmented regression model was used to estimate the effects of the temperature-humidity index (THI) on milk traits and elucidate the break point (BP) of the THI. To acquire the least-squares mean of milk traits, the generalized linear model was applied using fixed effects (region, calving year, calving month, parity, days in milk, and THI). For all parameters, the BP of THI was observed; in particular, milk production parameters dramatically decreased after a specific BP of THI (p < 0.05). In contrast, MUN and SCS drastically increased when THI exceeded BP in all cows (p < 0.05) and primiparous cows (p < 0.05), respectively. Dairy cows in South Korea exhibited negative effects on milk traits (decrease in milk performance, increase in MUN, and SCS) when the THI exceeded 70; therefore, detailed feeding management is required to prevent heat stress in dairy cows.

• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.2
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• pp.116-121
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• 2023

This study was conducted in Cheonan of central region in South Korea to evaluate the forage characteristics of early-maturing Italian ryegrass (IRG) within September, 2021 to June, 2023. The three different varieties of Italian ryegrass were prepared in this study 'Kogreen', 'Kospeed' and 'Kowinearly'. The results of heading date in this study, 'Kogreen' was the earliest in among cultivars and recorded 24th of April, whereas 'Kowinearly' was recorded the latest. In case of plant length parameter, 'Kowinearly' was the highest, in addition lodge tolerance score 'Kowinearly' also superior in whole cultivars. The dry matter yield of 'Kowinearly' was recorded significantly the highest (11,027 kg/ha), in contrast 'Kospeed' was recorded significantly the lowest (8,455 kg/ha). As a result of ADF and NDF content 'Kospeed' was recorded excellent value as compared the other two cultivars. The CP content of this study was excellent in the order of 'Kospeed' > 'Kowinearly' > 'Kogreen'. In case of the monosaccharides content 'Kogreen' had relatively higher glucose and fructose content than other four cultivars, therefore the 'Kogreen' has advantage for preparing high quality of silage. In conclusion, among the three different early varieties of Italian ryegrass, 'Kowinearly' was the superior in forage productivity, 'Kospeed' was the highest in feed value and 'Kospeed' had the highest in glucose and fructose content.

• Journal of English Language & Literature
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• v.57 no.6
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• pp.1151-1171
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• 2011

Conrad's novels, specifically the Lingard Trilogy-Almayer's Folly, An Outcast of the Islands, and The Rescue-and Lord Jim, set in the Southeast Asian or Malay Archipelago can be considered travel literature that played a significant role in British imperial expansion. Conrad's Malay novels were based not only on his experience in the region during his commercial journey but also on information from earlier travel writings about the Malays and their customs, including James Brooke's journals. The English traders in Conrad's novels, namely Lingard and Jim, were partly modeled on Brooke, the White Rajah, who founded and ruled the English colony on the northwest of Borneo in the 1840s. The white traders in Conrad's novels, who act as enlightened rulers, represent the British commercial expansionism, which was obscured by the phenomenon of the civilizing mission in the late nineteenth century. On the other hand, the colonial official Clifford's tales and novels about British Malaya demonstrate the typical travel accounts of the late nineteenth century that stress the civilizing mission over commercial exploitation. The concept of the enlightening mission was rooted in evolutionary anthropological thinking, which developed as part of the natural history in the early nineteenth century. In fact, the development of natural history, stimulating British expansion in search of commercially exploitable resources and lands, enabled travel writing as the collection of natural knowledge to become a profitable business. In Conrad, the white characters are mainly traders acting as colonial rulers, while in Clifford, they are scientific rulers with their commercial interests rarely apparent. In sum, Conrad's novels reveal that the new imperialism of the civilizing mission is still a commercial one, which disturbs rather than contributes to the imperial expansion-in contrast to other travel literature such as Clifford's.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.219-219
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• 2022

Granule-bound starch synthase I (GBSSI), encoded by the waxy gene, is responsible for the accumulation of amylose during the development of starch granules in rice endosperm. Despite many findings on waxy alleles, the genetic diversity and evolutionary studies are still not fully explored regarding their functional effects. Comprehensive evolutionary analyses were performed to investigate the genetic variations and relatedness of the GBSSI gene in 374 rice accessions composed of 54 wild accessions and 320 bred cultivars (temperate japonica, tropical japonica, indica, aus, aromatic, and admixture). GBSS1 coding regions were analyzed from a VCF file retrieved from whole-genome resequencing data, and eight haplotypes were identified in the GBSSI coding region of 320 bred cultivars. The genetic diversity indices revealed the most negative Tajima's D value in the tropical-japonica, followed by the aus and temperate-japonica, while Tajima's D values in indica were positive, indicating balancing selection. Diversity reduction was noticed in temperate japonica (0.0003) compared to the highest one (wild, 0.0044), illustrating their higher genetic differentiation by F_ST-value (0.604). The most positive Tajima's D value was observed in indica (0.5224), indicating the GBSSI gene domestication signature under balancing selection. In contrast, the lowest and negative Tajima's D value was found in tropical japonica (-0.5291), which might have experienced a positive selection and purified due to the excess of rare alleles. Overall, our study offers insights into haplotype diversity and evolutionary fingerprints of GBSSI. It ako provides genomic information to increase the starch content of cooked rice.

• The Journal of Advanced Prosthodontics
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• v.15 no.5
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• pp.259-270
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• 2023

PURPOSE. This study evaluated the reliability of the chair-side CAD-CAM surgical guide (CSG) in the anterior maxilla by comparing its accuracy with the laboratory 3D-printed surgical guide (3DSG) and manual surgical guide (MSG) concerning different levels of dentists' surgical experience. MATERIALS AND METHODS. Ten surgical guides of each type (MSG, 3DSG, and CSG) were fabricated on a control study model with missing right and left central incisors. Sixty implants were placed in 30 study models by two dentists (one inexperienced and one experienced) using three different types of surgical guides. Horizontal deviations at shoulder and at apex, vertical, and angular deviations were measured after superimposing the planned and placed implant positions in the software. Kruskal-Wallis and Mann-Whitney U tests were used to compare the accuracy of three types of surgical guides in each dentist group and the accuracy of each surgical guide between two dentists (α = .05). RESULTS. There were no significant differences in any deviations between CSG and 3DSG, apart from angular deviation, for both dentists' groups. Moreover, both CSG and 3DSG showed no significant differences in accuracy between the two dentists (P > .05). In contrast, MSG demonstrated significant differences from CSG and 3DSG and a significant difference in accuracy between the two dentists (P < .05). CONCLUSION. CSG provides superior accuracy to MSG in implant placement in the maxillary anterior region and is comparable to 3DSG at different levels of surgical experience, while offering the benefits of shorter manufacturing time and reduced patient visits.

• Coupled systems mechanics
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• v.12 no.6
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• pp.481-501
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• 2023

Over-coating is one of the most popular engineering practices to strengthen Reinforced Concrete (RC) structures, due to the relative quickness and ease of construction. It consists of an external coat bonded to the outer surface of the structural RC element, either by the use of chemical adhesives, mechanical anchor bolts or simply mortar injection. In contrast to these constructive advantages, the numerical estimation of the bearing capacity of the strengthened reinforced concrete element is still complicated, not only for the complexity of modelling a flexible membrane or plate attached to a quasi-rigid solid, but also for the difficulties that raise of simulating any potential delamination between both materials. For these reasons, the standard engineering calculations used in the practice remain very approximated and clumsy. In this work, we propose the formulation of a new 2D solid-layer finite element capable to link a solid body with a flexible thin layer, as it were the "skin" of the body, allowing the potential delamination between both materials. In numerical terms, this "skin" element is intended to work as a transitional region between a solid body (modelled with a classical formulation of a standard quadrilateral four-nodes element) and a flexible coat layer (modelled with cubic beam element), dealing with the incompatibility of Degrees-OfFreedom between them (two DOF for the solid and three DOF for the beam). The aim of the solid-layer element is to simplify the mesh construction of the strengthened RC element being aware of two aspects: a) to prevent the inappropriate use of very small solid elements to simulate the coat; b) to improve the numerical estimation of the real bearing capacity of the strengthened element when the coat is attached or detached from the solid body.