• Journal of Korean Institute of Industrial Engineers
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• v.29 no.1
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• pp.21-31
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• 2003

Determination of operational dimensions and tolerances is complex if there exist inconsistencies between operational and design specifications. Dimension and tolerance charts (D&T charts) have been used to establish the relationships among operational dimensions in complex machining. This chart proves that individual operations can be harmonized when they are interconnected. However, it is hard to generate the chart manually. Because operational dimensions and tolerances must meet the design specifications, the dimensions and tolerances of interconnected operations have to be verified serially for economical operations. In this paper, the chart is automatically generated from the interconnected operations. More importantly, all operational dimensions and tolerances displayed in the chart have been verified by using LP to meet the design specifications. Finally, the chart is converted to an operational routing sheet that contains a detailed process plan along with cutting speed, feed rate, and operational references based on material hardness, surface finish, and tool nose radius.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.12
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• pp.1782-1788
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• 2015

In this paper, analysis of the effects for construction tolerances on the current collection performance of high speed catenary system. The height of the contact wire is the geometrical position of the cantilever directly affects the current collection performance. Contact force when the height of the contact wire exceeds the construction tolerance were analyzed. As a result, the maximum contact force was analyzed to more than 350[N] that are recommended by EN50119. And when the geometrical position of the cantilever to exceeds the construction tolerance, the analysis results of uplift at the mast support points, it becomes 127[mm] that are recommended by UIC 799. If the construction tolerances exceeds the reference value, the current collection performance is deteriorated. Therefore, catenary system require high precision construction. In the future, there is a need for continuing research on the tolerance of catenary system in the actual operating state.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2198-2203
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• 2022

As robotics become more sophisticated, there are a growing number of generic systems being used for routine tasks in nuclear environments to reduce risk to radiation workers. The nuclear sector has called for more commercial-off-the-shelf (COTS) devices and components to be used in preference to nuclear specific hardware, enabling robotic operations to become more affordable, reliable, and abundant. To ensure reliable operation in nuclear environments, particularly in high-gamma facilities, it is important to quantify the tolerance of electronic systems to ionizing radiation. To deliver their full potential to end-users, mobile robots require sophisticated autonomous behaviors and sensing, which requires significant computational power. A popular choice of computing system, used in low-cost mobile robots for nuclear environments, is the UP Core single board computer. This work presents estimates of the total ionizing dose that the UP Core running the Robot Operating System (ROS) can withstand, through gamma irradiation testing using a Co-60 source. The units were found to fail on average after 111.1 ± 5.5 Gy, due to faults in the on-board power management circuitry. Its small size and reasonable radiation tolerance make it a suitable candidate for robots in nuclear environments, with scope to use shielding to enhance operational lifetime.

• Journal of People, Plants, and Environment
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• v.23 no.2
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• pp.171-178
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• 2020

The present study was conducted to determine the effects of electron beam irradiation on the postharvest quality of cut flowers. Cut flowers were irradiated with electron beam at 100, 200, 400, 600, 800, 1,000, and 2,000 Gy with a 10 MeV linear electron beam accelerator to evaluate their irradiation tolerance. Postharvest quality was determined by monitoring fresh weight loss, flower longevity, flower diameter, flowering rate, visual quality of flowers and leaves, and chlorophyll content. Cut flowers showed a radiation-induced damage with increasing the irradiation dose. Flower longevity and fresh weight of cut flowers decreased when the irradiation dose was increased. Flower bud opening was also inhibited in a dose-dependent manner. The effective irradiation doses for 10% reduction of postharvest quality (ED₁₀) values were 144.4, 451.6, and 841.2 Gy in the 'Medusa' lily, 'Montezuma' carnation, and 'Rosina White' eustoma, respectively. Although tolerance of cut flowers to electron beam irradiation vary according to species, cultivars, or maturity stage conditions, it is conceivable that 'Montezuma' carnation and 'Rosina White' eustoma could be tolerated and maintained overall postharvest quality up to 400 Gy, the generic irradiation dose approved by the Animal and Plant Health Inspection Service (APHIS) and the International Plant Protection Convention (IPPC) for postharvest phytosanitary treatments.

• Horticultural Science & Technology
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• v.35 no.2
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• pp.243-251
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• 2017

Plants have evolved to adapt to abiotic stresses, such as salt, cold, and drought stress. In this study, we conducted an in-depth analysis of drought resistance mechanisms by constructing a gene co-expression network in Chinese cabbage (Brassica rapa ssp. pekinensis L.). This drought stress co-expression network has 1,560 nodes, 4,731 edges, and 79 connected components. Based on genes that showed significant co-expression in the network, drought tolerance was associated with the induction of reactive oxygen species removal by raffinose family oligosaccharides and inositol metabolism. This network could be a useful tool for predicting the functions of genes involved in drought stress resistance in Chinese cabbage.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.4
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• pp.425-438
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• 2007

In this paper, unsettled technical controversies concerning about fatigue strength analysis for FPSO, one of the representative floaters, associated with welding types, screening methods, fabrication tolerances, corrosion margins and Morison loads are described based on yard practices. Basic theory for stochastic fatigue analysis is introduced as detail as possible. In order to resolve large parts of the controversies, a new fully stochastic fatigue analysis program for FPSO is developed.

• Clean Technology
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• v.23 no.3
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• pp.314-324
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• 2017

To verify the viability of Co, Ru and Zr-based catalyst for $CO_2$ (dry) reforming reaction, catalysts were fabricated using cordierite, silicon carbide and rota monolithic substrates, and they were compared with the conventional $Co-Ru-Zr/SiO_2$ catalyst in terms of performance and durability. Cordierite monolith was showed high activity with the least amount of active component. In addition, when Cordierite monolith was coated with Co-Ru-Zr in various ways, most excellent performance was showed at a precursor solution coating method. In particular, when 0.9 wt% Co-Ru-Zr/Cordierite was used for reaction, it was observed that 95% $CO_2$ conversion was maintained for 300 h at $900^{\circ}C$.

• Journal of the Korean Home Economics Association
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• v.5 no.1
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• pp.780-793
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• 1966

A study was made of influence of grandmother on the child's porsonality development. Behavior of randomly sampled 144 kindergarten children aged 5-6: 36 boys and 36 girls who came from general households were comparatively observed and rated by kindergartners who were able to correctly identify the children. Addition to this, interviews were conducted with their grandmothers by the auther. Rating scale used for behavior observations was consisted of 8 traits of personality: independency, dominance, co-operativeness, tolerance, responsibility, needs of achievement, agressiveness, and hostility. The scale for interviews was consisted of 3 domains of grandmothers attitude toward grandchildren; support, over control, and submissiveness. Both scales were carefully constructed and the validity of them were tested. The following results and conclusings were emerged from the study. 1. A moderate and statistically siggnificant relationships were found between the presence of grandmother and decline of dominance, tolerance, and needs of achievement of the boy and needs of achievement of the girl. Hostility of the girl increased by the presence of grandmother. 2. It was showed that most grandmothers inclined to support and submit to grandsons. 3. High negative correlations were obtained between anxiety of grandchildren and independency, cooperativeness, and needs of achievement of them.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.106-112
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• 2008

International conferences to block the spread of Avian bird flu occurred in Beijing, 2006 and others warned of the seriousness of the H5N1 strain. The meetings succeeded in generating billions of dollars from USA, EU and World Bank. Migratory birds seem to play a major role in the spread of the aggressive strain globally from Asia to Europe and Africa. Experiences of tolerance breeding of maize (Zea mays L.) for four decades against 20 biotic stresses suggest that the prime cause of the occurrence of H5N1 strain was due to the human beings' counter-efforts against nature. Excessive use of chemicals (spray and injection) in the commercial poultry farms had created high selection pressure on virus. The new strain had mutated for survival. Attempting to eliminate the virus by chemicals for 100% control is a dangerous way to control biotic stresses. This can create more aggressive strains. A solution would be to build up tolerability of the commercial animals against the virus. Improvement of poultry cage environments and respect for nature must be integrated. Potential foes must be watched.

• ALGAE
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• v.35 no.4
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• pp.375-388
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• 2020

Ocean acidification and warming, identified as environmental concerns likely to be affected by climate change, are crucial determinants of algal growth. The ichthyotoxic raphidophytes Chattonella species are responsible for huge economic losses and environmental impact worldwide. In this study, we investigated the impact of CO2 on the thermal performance curves (TPCs) of Chattonella marina and Chattonella ovata grown under temperatures ranging from 13 to 34℃ under ambient pCO2 (350 μatm) and elevated pCO2 (950 μatm). TPCs were comparable between the species or even between pCO2 levels. With the exception of the critical thermal minimum (CTmin) for C. ovata, CTmin for C. marina and the thermal optimum (Topt) and critical thermal maximum (CTmax) for both species did not change with elevation of pCO2 levels. While CO2 enrichment increased the maximum photosynthetic rates (Pmax) up to 125% at the Totp of 30℃, specific growth rates were not significantly different under elevated pCO2 for the two species. Overall, C. ovata is likely to benefit from climate change, potentially widening its range of thermal tolerance limit in highly acidic waters and contributing to prolonged phenology of future phytoplankton assemblages in coastal waters.