• Journal of Biosystems Engineering
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• v.23 no.3
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• pp.211-218
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• 1998

A variable flow-controlled boom sprayer was developed and evaluated. Field tests were conducted to evaluate the adoptability of the sprayerr with optimal conditions. Negative response time was obtained from the field test because pump and PTO were interlocked with the speed of sprayer. Another reason for the negative value was due to the definition of the response time. With constant on-time control, the system was unstable at the conditions of small tolerance and long control interval. The performances of the spray system were stable and accurate. The stable and synchronous responses were achieved with a variable on-time control. The flow control system with an optimal condition (1.0 sec of control interval, 2 of damping ratio, 1% of tolerance) provided the proper performance for uniform spraying. A standard operating procedure of the flow compensating boom sprayer for the ground speed variation was presented and recommended.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.718-721
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• 2001

For higher recording density in optical data storage, near field optics is being actively researched as one of the promising alternatives. But the tight assembling tolerance in NFR is one of big barriers to overcome for the realization of it. In this paper, the tolerances in assembling optic components of NFR system are analyzed. Some of key tolerances can be loosened by the optimization of objective lens design. But one of them become too tight by the optimization and should be controlled by other means. One of possible methods to control the tolerance is discussed.

• Transactions of the Society of Information Storage Systems
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• v.1 no.1
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• pp.67-72
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• 2005

This study proposes a design methodology to determine the optimum configurations of the optical flying head (OFH) for near-field recording systems. Since the OFH requires stricter static and dynamic characteristics of slider air-bearings within an optical tilt tolerance over the entire recording band, an optimum design to keep the focusing and tracking ability stable is essential. The desired flying characteristics considered in this study are to minimize the variation in flying height between the SIL and the disk from a target value, satisfying the restriction of the minimum flying height, to keep the pitch and roll angles within an optical tilt tolerance, and to ensure a higher air-bearing stiffness. Simulation results demonstrate the effectiveness of the proposed design methodology by showing that the static and dynamic flying characteristics of the optimally designed OFH are enhanced in comparison with those of the initial. The gap between the SIL and the disk can be kept at less than 100 nm even if the optical tilt tolerance of the SIL is considered.

• Journal of the Korea Safety Management & Science
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• v.13 no.1
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• pp.203-209
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• 2011

This study develops three new models that are practically applicable to three stages of Taguchi's robust design, which includes system design, parameter design and tolerance design. In system design, the Multiple Loss Function Analysis(MLFA) and Overall Loss Index(OLI) which reflect upon weight of characteristics and importance of specification are developed. Moreover parameter design presents Process Capability Index(PCI), $C_{PUK}$ and $C_{PLK}$, in order to segregate Signal-To-Noise Ratio(SNR) into accuracy and precision for an evaluation of relative comparison. In addition, tolerance design presents the new model of allowance computation for assembled product which is primarily derived from safety margin(SM) considering functional limit and specification. The guideline of those three new models, which include systematic charts and applicable illustrations, offers convenience for practitioners in the field. Hence, the practical applications could be made with the steps of robust designs such as system design, parameter design and specification allowance design.

• Journal of the Optical Society of Korea
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• v.16 no.3
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• pp.228-235
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• 2012

It is very important to analyze effectively the tolerance of an optical system with high resolution as the projection lens of photolithography or as the objective lens of a microscope. We would like to find an effective assembly structure and compensators to correct aberrations through global wavefront sensitivity analysis using Zernike polynomial expansion from the field and pupil coordinates rather than from only pupil coordinates. In this paper, we introduce global wavefront coefficients by small perturbations of the optical system, and analyze the optical performance with these coefficients. From this analysis, it is possible to see how we can enlarge the tolerance through the proper assembly structure and compensators.

• Nuclear Engineering and Technology
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• v.53 no.8
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• pp.2523-2533
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• 2021

In the last decade, the best estimate plus uncertainty methodologies in nuclear technology and nuclear power plant design have become a trending topic in the nuclear field. Since BEPU was allowed for licensing purposes by the most important regulator bodies, different uncertainty assessment methods have become popular, overall non-parametric methods. While non-parametric tolerance regions can be well stated and used in uncertainty quantification for licensing purposes, the propagation of the uncertainty through different codes (multi-scale, multiphysics) in cascade needs a better depiction of uncertainty than the one provided by the tolerance regions or a probability distribution. An alternative method based on the parametric or distributional probability boxes is used to perform uncertainty quantification and propagation regarding statistic uncertainty from one code to another. This method is sample-size independent and allows well-defined tolerance intervals for uncertainty quantification, manageable for uncertainty propagation. This work characterizes the distributional p-boxes behavior on uncertainty quantification and uncertainty propagation through nested random sampling.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.198-198
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• 2022

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.115-115
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• 2017

Zinc finger proteins constitute a large family which has been studied to have various functions in different organisms. Tandem CCCH zinc finger proteins (TZFs), members of the zinc finger protein family, are known to participate as post-transcriptional regulators of gene expression in eukaryotes. Here, we showed that the OsZn15, a gene for tandem CCCH zinc finger protein, is induced by abiotic stress and its overexpression in transgenic rice plants (PGD1:OsZn15) gains higher drought tolerance. Gene expression analysis of promoter:GFP plants revealed that OsZn15 is specifically expressed in anther and embryo, but not in vegetative organs. In-field evaluation, grain yield was higher in the PGD1:OsZn15 than nontransgenic plants under drought conditions. Interestingly, OsZn15 is shown to not only localize at nucleus but also co-localize with both processing bodies (PB) and stress granules (SG), two messenger ribo-nucleoprotein complexes which are known to activate by forming cytoplasmic foci under stress conditions. In sum, these results suggest that OsZn15 increases drought stress tolerance of rice probably by participating in RNA turnover in PB and SG.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.2
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• pp.67-72
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• 2005

Overwintering capacity, closely related to winter hardiness, of Chinese milk vetch planted with different sowing times and sowing practices was investigated to improve the incorporation into cropping system in Korea. The tolerance to low temperature was evaluated with $LT_50$ using leaf disc leaching method. Dry weight of CMV was reduced remarkably with delayed planting from Sep. 5 to Oct. 20. The differences in tolerance to freezing temperature were not conspicuous among CMV genotypes, however, the differences between genotype (collections at different regions) were due to the plant architecture, mainly to the leaf angle. The crouching genotype collected at central region of Korean peninsula, which showed excellent freezing tolerant, has planophile leaves. The feature of internal constituents of CMV genotypes did not show any noticeable differences with respect to the freezing tolerance which evaluated by leaf disc leaching experiment. To overcome the poor overwintering capacity, tolerant genotype should be developed by selection with considering the plant architecture. The reduction of CMV growth during overwintering period was ameliorated with furrow-sowing under late-sown condition, therefore, when the CMV is inevitably sown late after recommended time, the seeds should be sown on furrow to overcome the cold stress.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.129-133
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• 1999

Excessive soil water at vegetative growth stages during the rainy season induces yield losses in soybeans. Our objectives were to obtain basic information about the cultivar differences and to understand the stress-tolerance process for due to excessive soil water. Previous experiments revealed soybean genotypic differences in tolerance to excessive soil water. A field experiment was conducted at the Research Farm of Korea University near Seoul on 21 May 1998. Soybean[Glycine max (L.) Merrill] cultivars, 'Hannamkong' (sensitive) and 'Taekwan-gkong'(tolerant) were planted in vinyl-lined plots(1.2 x 4.2 x 0.3 m deep) and control plots. Drip irrigation began at VI growth stage to submerge the soil surface. Three weeks of excessive soil water treatment reduced all growth parameters measured to soybean plants. Excessive soil water stress resulted in decreases of N, P, K, Ca, Mg and Cu, and increases of Fe and Mn contents in soybean leaves. The stress index of tolerant cultivars under excessive soil water showed no large difference in soybean growth characteristics measured at three growth stages. However, K, Ca, Mg, Fe and Mn contents in soybean leaves appeared to differ between sensitive and tolerant cultivars. From the above results, stress and tolerance indices are proposed for a method to test cultivar differences in plant responses within a species under adverse growth environments.