• Korean Journal of Plant Tissue Culture
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• v.27 no.4
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• pp.339-343
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• 2000

When plants are exposed to subfreezing temperatures ice crystals are forming within extracelluar space in leaves. The growth of ice crystal is closely related to the degree of freezing injury. It was shown that an antifreeze protein binds to an ice nucleator through hydrogen bonds to prevent growth of ice crystal and also reduces freezing damage. The antifreeze proteins in plants are similar to PR proteins but only the PR proteins induced upon cold acclimation were shown to have dual functions in antifreezing as well as antifungal activities. Three of the genes encoded for CLP, GLP, and TLP were isolated from barley and Kentucky bluegrass based on amino acid sequence revealed after purification and low temperature-inducibility as shown in analysis of the protein. The deduced amino acid of the genes cloned showed a signal for secretion into extracellular space where the antifreezing activity sup-posed to work. The western analysis using the antisera raised against the antifreeze proteins showed a positive correlation between the amount of the protein and the level of freeze tolerance among different cultivars of barely. Besides it was revealed that TLP is responsible for a freeze tolerance induced by a treatment of trinexapac ethyl in Kentucky bluegrass. Analysis of an overwintering wild rice, Oryza rufipogon also showed that an acquisition of freeze tolerance relied on accumulation of the protein similar to CLP. The more direct evidence for the role of CLP in freeze tolerance was made with the analysis of the transgenic tobacco showing extracellular accumulation of CLP and enhanced freeze tolerance measured by amount of ion leakage and rate of photosynthetic electron transport upon freezing. These antifreeze proteins genes will be good candidates for transformation into crops such as lettuce and strawberry to develop into the new crops capable of freeze-storage and such as rose and grape to enhance a freeze tolerance for a safe survival during winter.

• Current Optics and Photonics
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• v.1 no.5
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• pp.474-490
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• 2017

Since the recent slowdown in the smartphone market, studies for wearable devices are briskly being carried out to find new markets, such as virtual reality devices. In this paper, a head-mounted display (HMD) which provides expanded virtual images before human eyes by enlarging images of a small display was designed, and the tolerance analysis method for a focus-adjustable HMD based on afocal optical systems was studied. There are two types of HMDs: a see-through type that allows the user to view the surroundings, and a see-close type where the user can only view the display screen; the former is used in this study. While designing the system, we allowed a lens within the system to be shifted to adjust its focus from +1 to -4 D (diopters). The yield of the designed systems was calculated by taking the worst-case scenario of a uniform distribution into account. Additionally, a longitudinal aberration was used rather than MTF for the tolerance analysis with respect to system performance. The sensitivity of the designed system was calculated by assigning a certain tolerance, and the focus lens shift was calculated to adjust the image surface variations resulting from the tolerance. The smaller the tolerance, the more expensive the unit price of the products. Very small tolerances may even be impossible to fabricate. Considering this, the appropriate tolerance was assigned; the maximum shift of the focus lens in which the image surface can be adjusted was obtained to find the changes in aberration and a good yield.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.5
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• pp.527-537
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• 2016

Recent automakers are trying to be more precise with the dimension check and moving parts to guarantee high quality and satisfy customer requirements. The aim of this paper is to investigate the design tolerance suitability of door operating mechanism linked arms, lever, and cam-shaft in a mobile air handling unit. These parts are complicated because doors, arms, lever and cam-shaft are connected nonlinearly in 3D. The current tolerance analysis method poses problems in design analysis because the moving doors are reasonably suitable for the AHU function. The 3-DCS analysis method provided useful results not only in establishing the inspection criteria for the quality control of products but also in enabling economical production. As a result, the vent door had $1.62^{\circ}{\sim}1.72^{\circ}$ and the defrost door had $0.84^{\circ}{\sim}0.9^{\circ}$ for the directly connected arms operating-type. For the lever connected arm operating-type, the foot door had $2.0^{\circ}{\sim}2.24^{\circ}$ tolerance, while the tolerance values satisfied the air flow volume distribution rate criteria in the AHU. Finally, the results have confirmed the design's tolerance suitability by using 3-DCS analysis at the early design stages. Reliability can be achieved by analyzing accumulated tolerance during the sub-parts assembly process and the moving mechanism linked especially by arms, lever, and cam-shaft.

• Plant Biotechnology Reports
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• v.2 no.1
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• pp.41-46
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• 2008

Salinity stress is a major limiting factor in cereal productivity. Many studies report improvements in salt tolerance using model plants, such as Arabidopsis thaliana or standard varieties of rice, e.g., the japonica rice cultivar Nipponbare. However, there are few reports on the enhancement of salt tolerance in local rice cultivars. In this work, we used the indica rice (Oryza sativa) cultivar BR5, which is a local cultivar in Bangladesh. To improve salt tolerance in BR5, we introduced the Escherichia coli catalase gene, katE. We integrated the katE gene into BR5 plants using an Agrobacterium tumefaciens-mediated method. The introduced katE gene was actively expressed in the transgenic BR5 rice plants, and catalase activity in $T_1$ and $T_2$ transgenic rice was approximately 150% higher than in nontransgenic plants. Under NaCl stress conditions, the transgenic rice plants exhibited high tolerance compared with nontransgenic rice plants. $T_2$ transgenic plants survived in a 200 mM NaCl solution for 2 weeks, whereas nontransgenic plants were scorched after 4 days soaking in the same NaCl solution. Our results indicate that the katE gene can confer salt tolerance to BR5 rice plants. Enhancement of salt tolerance in a local rice cultivar, such as BR5, will provide a powerful and useful tool for overcoming food shortage problems.

• The Journal of the Korea Contents Association
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• v.19 no.4
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• pp.638-650
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• 2019

This study collected 328 self-reporting questionnaires from the married middle-aged women residing in Seoul, Gyeonggi and Daejeon province to explore the mediating effects between distress tolerance and rumination in the relations of life stress and depression. SPSS 20.0 and AMOS 20.0 were used to analyze descriptive statistics, correlation, and structural equation. Following is the summarizaton of the study. First, the life stress showed a significant positive correlation with rumination and depression, and meaningful negative correlation wiith distress tolerance. Also, it showed negative correlation with distress tolerance and rumination. Second, each distress tolerance and rumination showed meaningful mediating effects in the relations of life stress and depression. Third, dual mediating effect of distress tolerance and rumination is showed meaningful in the relations of life stress and depression. Based on the results above, we verified that three variables, life stress, distress tolerance and rumination, affect depression significantly in married middle-aged women and discussed the significance of this result, limitations and suggestions for future studies.

• Korean Journal of Culture and Social Issue
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• v.28 no.3
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• pp.307-329
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• 2022

This study aimed to explore factors which can predict interpersonal tolerance and intolerance. Specifically, the study examined whether tolerance and intolerance would be explained by demographic variables, social desirability, empathy (cognitive empathy and affective empathy), fear of compassion for others, social trust, and zero-sum belief. Participants in the study were 445 adults (218 males and 227 females) who completed an online survey. Data were analyzed by using hierarchical regression analyses to control the effects of demographic variables and social desirability. The results indicated that tolerance was explained by gender, subjective socioeconomic status, social desirability, cognitive empathy, and social trust. In addition, intolerance was predicted by social desirability, fears of compassion for others, and zero-sum belief. It means that the constructs of tolerance and intolerance are distinct, and different factors predict tolerance and intolerance, respectively. Therefore, it would be necessary to develop realistic ways to promote tolerance and to prevent intolerance at the same time in order to achieve co-existence in a multicultural and diverse society.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.213-213
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• 2022

Pre-harvest sprouting(PHS) refers to germinating seeds in the mother plant before harvesting under low dormancy and humid climate, deteriorating grain quality, and rice yield. Rice varieties with floury endosperm(RFE) have been developed to boost domestic rice consumption by invigorating the processed rice industry, reducing milling and environmental cost. However, the PHS tolerance of RFE is relatively low in the rice varieties with transparent endosperm(RTE) since they soak moisture rapidly due to soft endosperm. In this study, Baromi2(BR2), floury endosperm, and Jomyeong1(JM1), PHS tolerance donor, were crossed to improve PHS tolerance. Major agronomic traits and PHS tolerance test of ten F₇(BR2/JM1) lines were conducted in NICS, 2022. The evaluations of PHS were carried out according to the method of RDA(2012) with slight modifications. Briefly, three panicles were treated and incubated 25℃ in a growth chamber 35 days after the heading date. Ten PHS tolerance promising lines demonstrated floury endosperm. The heading date of BR2 and JM1 was 7/27 and 8/5, respectively. The heading date of promising lines was 7/23~8/10. The PHS rate of BR2 and JM1 exhibited 56.3% and 10.7%, respectively. However, the PHS rate often promising lines demonstrated 2.4%~52.4%, 3 lines significantly lower than BR2. Further studies such as ABA contents are necessary to elucidate the mechanism of PHS tolerance in BR2/JM1. These results may contribute to developing elite RFE lines with improved PHS tolerance.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.195-195
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• 2022

Abiotic stress is a major problem in global agriculture as it negatively affects crop growth, yield, and quality. Wheat (Triticum aestivum) is the world's second-highest-producing food resource, so the importance of mitigating damage caused by abiotic stress has been emerging. In this study, we performed GWAS to search for SNPs associated with salt tolerance and drought tolerance. NaCl (200 mM) treatment was performed at the seedling stage using 613 wheat varieties in Korean wheat core collection. Root length, root surface area, root average diameter, and root volume were measured. Drought stress was applied at the seedling stage, and the above phenotypes were measured. GW AS was performed for each phenotype data using the MLM, MLMM, and FarmCPU models. The best salt-tolerant wheat varieties were 'MK2402', 'Gyeongnam Geochang-1985-3698', and 'Milyang 13', showing superior root growth. The significant SNP AX-94704125 (BA00756838) were identified in all models. The genes closely located to the significant SNP were searched within ± 250 kb of the corresponding SNP. A total of 11 genes were identified within the region. NB-ARC involved in the defense response, FKSI involved in cell wall biosynthesis, and putative BP Ml involved in abiotic stress responses were discovered in the 11 genes. The best drought-tolerant wheat varieties were 'PI 534284', 'Moro of Sind', and 'CM92354-33M-0Y-0M-6Y-0B-0BGD', showing superior root growth. This study discovered SNPs associated with salt tolerance in Korean wheat core collection through GWAS. GWAS of drought tolerance is now proceeding, and the GWAS results will be represented on a poster. The SNPs identified by GWAS can be useful for studying molecular mechanisms of salt tolerance and drought tolerance in wheat.

• Journal of Plant Biotechnology
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• v.5 no.3
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• pp.157-161
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• 2003

Proline is known as an osmoprotectant accumulating in response to salt and dehydration stresses. An increased level of proline is achieved by either an induced synthesis or a reduced degradation of proline. In an attempt to increase salt tolerance in carrot, a P5CS gene from mothbean was introduced via an Agrobacterium-mediated transformation. The resulting carrot cells and the regenerated plants containing the transgene showed increased levels of proline compared to nontransgenics. The transgenic cell line, Pj2 showed about 6 times increased degree of tolerance determined by relative growth after a treatment in 250 mM NaCl. In facts, due to the retarded growth shown in non-saline condition, Pj2 cells grow only about 1.2 times better than nontransgenic control under salt stress condition. Taken together, it appears that a P5CS is a key enzyme in proline biosynthesis and the increased accumulation of proline by overexpression of the enzyme is enough to enhance tolerance to salt stress in carrot.

• ETRI Journal
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• v.24 no.1
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• pp.12-22
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• 2002

A Mobile IP allows IP hosts to move between different networks without changing their IP addresses. Mobile IP systems supporting local registration were introduced to reduce the number of times a home registration with the remotely located home agent was needed. The local registration Mobile IP scheme enhanced performance by processing registration requests of mobile nodes at a local agent. The local registration approach may affect other aspects of the Mobile IP systems such as fault tolerance. In this paper, we briefly review previous solutions for supporting fault tolerance in local registration Mobile IP systems and propose a fault tolerance protocol with a backup foreign agent in a hierarchical local registration mobile IP to enhance the efficiency of such systems against foreign agent failures. We also describe the specification of the proposed protocol using LOTOS and perform its validation using MiniLite. Finally, we analyze the performance of our proposed fault tolerance protocol through simulation.