• BMB Reports
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• v.38 no.4
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• pp.440-446
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• 2005

A cDNA that was rapidly induced upon abscisic acid, cold, drought, mechanical wounding and to a lesser extent, by high salinity treatment, was isolated from Arabidopsis seedlings. It was classified as DREB subfamily member based on multiple sequence alignment and phylogenetic characterization. Since it encoded a protein with a typical ERF/AP2 DNA-binding domain and was closely related to the TINY gene, we named it TINY2. Gel retardation assay revealed that TINY2 was able to form a specific complex with the previously characterized DRE element while showed only residual affinity to the GCC box. When fused to the GAL4 DNA-binding domain, either full-length or its C-terminus functioned effectively as a trans-activator in the yeast one-hybrid assay while its N-terminus was completely inactive. Our data indicate that TINY2 could be a new member of the AP2/EREBP transcription factor family involved in activation of down-stream genes in response to environmental stress.

• Steel and Composite Structures
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• v.19 no.6
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• pp.1501-1510
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• 2015

The frequency selective surface (FSS) embedded hybrid composite materials have been developed to provide excellent mechanical and specific electromagnetic properties. Radar absorbing structures (RASs) are an example material that provides both radar absorbing properties and structural characteristics. The absorbing efficiency of an RAS can be improved using selected materials having special absorptive properties and structural characteristics and can be in the form of multi-layers or have a certain stacking sequence. However, residual stresses occur in FSS embedded composite structures after co-curing due to a mismatch between the coefficients of thermal expansion of the FSS and the composite material. In this study, to develop an RAS, the thermal residual stresses of FSS embedded composite structures were analyzed using finite element analysis, considering the effect of stacking sequence of composite laminates with square loop (SL) and double square loop (DSL) FSS patterns. The FSS radar absorbing efficiency was measured in the K-band frequency range of 21.6 GHz. Residual stress leads to a change in the deformation of the FSS pattern. Using these results, the effect of transmission characteristics with respect to the deformation on FSS pattern was analyzed using an FSS Simulator.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.7 no.1
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• pp.42-59
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• 2000

This study was done to analyze and develop the concept of coping in patients receiving hemodialysis. The Hybrid Model of concept development was applied to develop a conceptual structure of coping in patients receiving hemodialysis, which included a field study carried out using an in-dept interview with 18 patients in the hemodialysis room of one general hospital in Seoul. Data-analysis was done in three phases as suggested by the Hybrid Model. Finally, by summarizing the results from each case, the attributes of coping, its dimensions, definition and structure were outlined. According to the results of the study, a conceptual structure of coping which centers around stressors, stress-appraisal, strategy of coping and new definitions of coping in patients receiving hemodialysis was suggested : The coping of patients receiving hemodialysis is a process that deals with physical, emotional, inter-personal, and role stress caused by hemodialysis due to renal failure. It has a series of phases which include a phase that appraises the stressful situation based on past experience of chronic disease management, one's remaining rears, the extent of family support, the extent of economic dependency, inter-personal support. education and uncertainty, and a phase of developing coping strategies that con be affected by social support and self esteem. As a result of coping, patients adapt or not to the life situation of receiving hemodialysis.

• Journal of Plant Biotechnology
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• v.41 no.1
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• pp.26-32
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• 2014

Recent genome annotation revealed that Populus trichocarpa contains 81 glutathione S-transferase (GST) genes. GST genes play important and varying roles in plants, including conferring tolerance to various abiotic stresses. Little information is available on the relationship - if any - between drought/salt stresses and GSTs in woody plants. In this study, we screened the PatgGST genes in hybrid poplar (Populus alba ${\times}$ Populus tremula var. glandulosa) that were predicted to confer drought tolerance based on our expression analysis of all members of the poplar GST superfamily following exposure to salt (NaCl) and drought (PEG) stresses, respectively. Exposure to the salt stress resulted in the induction of eight PatgGST genes and down-regulation of one PatgGST gene, and the level of induction/repression was different in leaf and stem tissues. In contrast, 16 PatgGST genes were induced following exposure to the drought (PEG) stress, and two were down-regulated. Taken together, we identified seven PatgGSTs (PatgGSTU15, PatgGSTU18, PatgGSTU22, PatgGSTU27, PatgGSTU46, PatgGSTU51 and PatgGSTU52) as putative drought tolerance genes based on their induction by both salt and drought stresses.

• Korean Journal of Plant Resources
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• v.30 no.5
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• pp.571-577
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• 2017

Abscisic acid (ABA) is an important phytohormone involved in abiotic stress tolerance in plants. The group A bZIP transcription factors play important roles in the ABA signaling pathway in Arabidopsis but little is known about their functions in rice. In our current study, we have isolated and characterized a group A bZIP transcription factor in rice, OsABF3 (Oryza sativa ABA responsive element binding factor 3). We examined the expression patterns of OsABF3 in various tissues and time course analysis after abiotic stress treatments such as drought, salinity, cold, oxidative stress, and ABA in rice. Subcellular localization analysis in maize protoplasts using a GFP fusion vector further indicated that OsABF3 is a nuclear protein. Moreover, in a yeast one-hybrid experiment, OsABF3 was shown to bind to ABA responsive elements (ABREs) and its N-terminal region found to be necessary to transactivate a downstream reporter. A homozygous T-DNA insertional mutant of OsABF3 is more sensitive to salinity, drought, and oxidative stress compared with wild type plants ＆ OsABF3OX plants. In addition, this Osabf3 mutant showed a significantly decreased sensitivity to high levels of ABA at germination and post-germination. Collectively, our present results indicate that OsABF3 functions as a transcriptional regulator that modulates the expression of abiotic stress-responsive genes through an ABA-dependent pathway.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.2
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• pp.193-203
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• 2014

Temperature-dependent stress analysis and heat transfer analysis of a rotating gas turbine blade made of functionally graded materials (FGMs) are presented considering turbine operating temperature and ceramic particle size. The material properties of functionally graded materials are assumed to vary continuously and smoothly across the thickness of the thin-walled blade. For obtaining system stiffness reflecting these characteristics, the one-dimensional heat transfer equation is applied along the thickness of the thin-walled blade for determining the temperature distribution. Using the results of the temperature analysis, the equations of motion of a rotating blade are derived with hybrid deformation variable modeling method along with the Rayleigh-Ritz assumed mode methods. The validity of the derived rotating blade model is evaluated by comparing its transient responses and temperature distribution with the results obtained using a commercial finite element code. The maximum tensile stress with operating speed and gradient index are obtained. Furthermore, the gradient index that minimizes blade temperature was investigated.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.6
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• pp.33-38
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• 2008

Most structures of vehicle are composed of many substructures connected to one another by various types of mechanical joints. In vehicle engineering, it is important to study these jointed structures under random frequency vibration for the evaluations of fatigue life and stress concentration exactly. It is rarely obtained the accurate load history of specified positions in a jointed structure because of the errors such as modeling, measurement, and etc. In the beginning of design, exact load data are actually necessary for the fatigue strength and life analysis to minimize the cost and time of designing. In this paper, the hybrid method of practical dynamic load determination is developed by the combination of the principal stresses from F. E. Analysis and test of a jointed structure. Least square pseudo inverse matrix is adopted to obtain an inverse matrix of analyzed stresses matrix. The error minimization method utilizes the inaccurate measured error and the shifting error that the whole data is stiffed over real data. The least square criterion is adopted to avoid these errors. Finally, to verify the proposed system, a heavy-duty bus is analyzed. This measurement and prediction technology can be extended to the different jointed structures.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.05a
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• pp.9-12
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• 2002

A parametric study has been conducted to investigate the effect of the geometry on the strength of an unidirectional and fabric hybrid laminated composite joint. Tests are conducted for the specimens with nine different edge-to-hole diameter or width-to-hole diameter ratios. For the finite element analysis, the characteristic length method is used, and the tests for determining the characteristic length are performed additionally. Nonlinear contact problem between the pin and laminate is modeled by the gap element in MSC/NASTRAN. Tsai-Wu failure criteria is applied to the stress on the characteristic curve. The finite element and experimental results shows good agreement in strength of composite joint. Results of the parametric study shows the effect of the geometry is remarkable in the specimens with width-to-hole diameter ratio less than 2.8 and edge-to-hole diameter ratio less than 1.4.

• Advances in concrete construction
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• v.9 no.2
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• pp.125-137
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• 2020

As confining materials for concrete, steel and fibre-reinforced polymer (FRP) composites have important applications in both the seismic retrofit of existing reinforced concrete columns and in the new construction of composite structures. We present a comprehensive review of the axial stress-strain behaviour of the FRP-confined concrete column. Next, the mechanical performance of the hybrid FRP-confined concrete-steel composite columns are comprehensively reviewed. Furthermore, the results of FRP-confined concrete column experiments and FRP-confined circular concrete-filled steel tube experiments are presented to study the interaction relationship between various material sections. Finally, the combinations of material sections are discussed. Based on these observations, recommendations regarding future research directions for composite columns are also outlined.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.464-469
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• 2000

In order to analyze effectively the discontinuous parts such as holes or notches included in mechanical structures by the finite element method, a singular finite element for orthotropic materials. is proposed. This singular element is formulated by the Trefftz method and the hybrid variational principles, which the displacements and stresses are simultaneously assumed using the Trefftz functions. Through several numerical tests, it is shown that the proposed singular element is very efficient for the accurate stress analysis of the various types of discontinuous parts.