• Steel and Composite Structures
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• v.47 no.2
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• pp.167-184
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• 2023

In this study, a new recentering friction device (RFD) to retrofit steel moment frame structures is introduced. The device provides both self-centering and energy dissipation capabilities for the retrofitted structure. A hybrid performance-based seismic design procedure considering multiple limit states is proposed for designing the device and the retrofitted structure. The design of the RFD is achieved by modifying the conventional performance-based seismic design (PBSD) procedure using computational intelligence techniques, namely, genetic algorithm (GA) and artificial neural network (ANN). Numerous nonlinear time-history response analyses (NLTHAs) are conducted on multi-degree of freedom (MDOF) and single-degree of freedom (SDOF) systems to train and validate the ANN to achieve high prediction accuracy. The proposed procedure and the new RFD are assessed using 2D and 3D models globally and locally. Globally, the effectiveness of the proposed device is assessed by conducting NLTHAs to check the maximum inter-story drift ratio (MIDR). Seismic fragilities of the retrofitted models are investigated by constructing fragility curves of the models for different limit states. After that, seismic life cycle cost (LCC) is estimated for the models with and without the retrofit. Locally, the stress concentration at the contact point of the RFD and the existing steel frame is checked being within acceptable limits using finite element modeling (FEM). The RFD showed its effectiveness in minimizing MIDR and eliminating residual drift for low to mid-rise steel frames models tested. GA and ANN proved to be crucial integrated parts in the modified PBSD to achieve the required seismic performance at different limit states with reasonable computational cost. ANN showed a very high prediction accuracy for transformation between MDOF and SDOF systems. Also, the proposed retrofit showed its efficiency in enhancing the seismic fragility and reducing the LCC significantly compared to the un-retrofitted models.

• Anxiety and mood
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• v.11 no.2
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• pp.91-105
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• 2015

Objectives : After disaster, some people develop posttraumatic stress sequelae such as posttraumatic stress disorder (PTSD), major depression, substance use disorders, and suicide. To date, numerous screening and assessment tools for behavioral health issues including mental health problems, psychosocial maladjustment and status of recovery after disaster have been developed. In this condition, one of important topics is to choose instruments that can quickly and accurately measure the issues. Methods : This article reviewed several self-reported scales in adults for disaster behavioral health, which were searched using academic search engines like PubMed, Scopus, KoreaMed and KISS from the earliest available date of indexing through January 31, 2015. Results : More than 40 eligible instruments evaluating the disaster behavioral health issues containing posttraumatic stress sequelae, psychological and social resources, non-disaster stress, and general functions were presented in terms of availability, effectiveness, and expeditiousness. Also, we introduced basic frame aiming on practical usage, which includes standard version and brief version of the instruments for disaster behavioral health. Conclusion : We suggest the accessibility and the applicability of assessment instruments for disaster behavioral health. The systemic review of this article will provide further directions for them.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.102-111
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• 2016

The goal of this study was to characterize the BrDSR (Drought Stress Resistance in B. rapa) gene and to identify the expression network of drought-inducible genes in Chinese cabbage under drought stress. Agrobacterium-mediated transformation was conducted using a B. rapa inbred line ('CT001') and the pSL100 vector containing the BrDSR full length CDS (438 bp open reading frame). Four transgenic plants were selected by PCR and the expression level of BrDSR was approximately 1.9-3.4-fold greater than that in the wild-type control under drought stress. Phenotypic characteristics showed that BrDSR over-expressing plants were resistant to drought stress and showed normal growth habit. To construct a co-expression network of drought-responsive genes, B. rapa 135K cDNA microarray data was analyzed to identify genes associated with BrDSR. BrDSR was directly linked to DARK INDUCIBLE 2 (DIN2, AT3G60140) and AUTOPHAGY 8H (ATG8H, AT3G06420) previously reported to be leaf senescence and autophagy-related genes in plants. Taken together, the results of this study indicated that BrDSR plays a significant role in enhancement of tolerance to drought conditions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.5
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• pp.599-606
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• 2022

Strain gauges and the bridge weigh-in-motion (BWIM) method are the representative field measurement methods used for fatigue evaluationsof a steel bridge-in-service. For a fatigue reliability evaluation to assess fatigue damage accumulation, the effective stress range and the number of stress cycles applied as the fatigue details can be estimated based on the AASHTO Manual for Bridge Evaluations with the field measurement data of the target bridge. However, the procedure for estimating the effective stress range and the stress cycles from field measurement data has not been explicitly presented. Furthermore, studies that quantitatively compare differences in fatigue evaluation results according to the field measurement data type or processing method used are still insufficient. Here, a fatigue reliability evaluation is conducted using strain and BWIM data that are measured simultaneously. A frame model and a shell-solid model were generated to examine the effect of the accuracy of the structural analysis model when using BWIM data. Also, two methods of handling BWIM data when estimating the effective stress range and average daily cycles are defined. As a result, differences in evaluation results according to the type of field measurement data used, the accuracy of the structural analysis model, and the data handling method could be quantitatively confirmed.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.323-328
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• 2003

Soil salinity is one of the most serious abiotic stresses limiting the productivity of agricultural crops. To cope with salt stress, plants respond with physiological, developmental and biochemical changes, including the synthesis of a number of proteins and the induction of gene expression. Salicornia herbacea is a halophytic plant that grows in salt marshes and on muddy seashores. In order to understand the biochemical and molecular mechanisms of salt tolerance in S. herbacea, we isolated several genes that involved in the salt tolerance by mRNA differential display. Here we report the cloning of a cDNA encoding fructose-1, 6-bisphosphate aldolase, named ShADL, which is 1293 bp long and contains an open reading frame consisted of 359 amino acids with calculated molecular mass of 39 kDa. ShADL protein showed 86％ identity with Arabidopsis and 78％ with aldolase of common ice plant. Northern blot analysis revealed that the transcript of ShADL gene was increased dramatically depending on the NaCl concentrations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.2242-2248
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• 2015

The damages from greenhouses collapsing due to heavy snowfall in winter are increasing, and the current frames of greenhouse are required to be improved. This study was conducted to seek solutions to improve intensities of greenhouse frame to bear heavy snows. We investigated a structural safety of greenhouses by calculating axial force, bending moment and combined stress when snow load was increased up to 30% of the current standard ground snow load of the conventional greenhouse types (07-single type 3, 07-single type 18) in the three regions (Gyeongju, Sokcho, and Gangneung) where were most damaged by recent heavy snows. In addition, we determined what structural type was most efficiently bear snow loads by measuring the differences between the load bearing strength according to the changes of tube diameter and thickness or the rafter spacing of greenhouses circular pipe. MIDAS GEN program was used in the analysis. As a result, with the snow load increase of 30%, greenhouse in Gyongju was still safe, but in Sokcho was at a risk, and in Gangneung was possible to be collapsed even in the current snow load. Increased pipe diameter than increased pipe thickness was more efficient in terms of improved performance of greenhouse structure. Accordingly, it is suggested to revise standards of greenhouse to increase pipe diameter of rafter for minimizing damages by heavy snow.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.1
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• pp.176-182
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• 2018

The purpose of this study was to investigate the safety and rationality of buckling strength and length coefficient by comparing with the design standards of domestic and foreign compression materials based on the buckling test results of circular steel pipe with ball joints. The types of round steel pipes selected for buckling performance evaluation were ø$48.6{\times}2.8t$, ø$60.5{\times}3.2t$ and ø$76.3{\times}3.2t$. For the design of domestic and foreign compression materials, Korea 's Load Resistance and Factor Design, Japan' s Limit State Design, and British Standard BS5950 standard were applied. In this study, we compared and analyzed the buckling performance between the experimental results of the previous research and the domestic and foreign design standards. The results were summarized as follows. As a result of applying the full length of the member to the buckling length in the compression materials design standards of each country, it was 64-89% of the buckling strength by the experiment. Therefore, it is deemed desirable to perform the member design according to the current design standard formula for safety. Experimental results show that the measured buckling strength was 1.02-1.43 times higher than the buckling strength of pure cylindrical steel tubes in the design standards of Korea, Japan and the United Kingdom compression materials. Consequently, it seemed that the buckling strength of individual member in the design of space frame structure should be considered buckling coefficient as the length of pure round steel pipe rather than the length of inter-node.

• Journal of Digital Convergence
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• v.12 no.4
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• pp.33-41
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• 2014

This study conducted a survey 212 adolescents in multi-cultural family to measure the level of their discrimination experience and acculturation stress by comparing with social integration analysis frame of D. Heater and examined how it affects them to national identity. Followings are the main results of this study. First, after measuring the discrimination experience level of those surveyed, their average was a bit higher than the normal level, showing 2.63(SD=.72), and their acculturation stress was 2.48(SD=.65) which is average. Second, their level of national identity showed 2.16(SD=.57), which was lower than the normal level, and there was statistically a meaningful difference between the groups depending on their academic level, parents' marital status, mother's Korean ability. Third, the factors that affected in national identity were in the order of their discrimination experience(${\beta}$=-.305), parents' marital status(${\beta}$=.286), acculturation stress(${\beta}$=-.225), academic level(${\beta}$=.186), mother's Korean ability(${\beta}$=.173). Based on these results, several ways are suggested to improve national identity of adolescents in multi-cultural family.

• BMB Reports
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• v.39 no.3
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• pp.253-262
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• 2006

Parkinson's disease (PD) is a common neurodegenerative disorder and is characterized by the progressive loss of dopaminergic neurons in the substantia nigra. Although many studies showed that the aggregation of $\alpha$-synuclein might be involved in the pathogenesis of PD, its protective properties against oxidative stress remain to be elucidated. In this study, human wild type and mutant $\alpha$-synuclein genes were fused with a gene fragment encoding the nine amino acid trans activator of transcription (Tat) protein transduction domain of HIV-l in a bacterial expression vector to produce a genetic in-frame WT Tat-$\alpha$-synuclein (wild type) and mutant Tat-a-synucleins (mutants; A30P and A53T), respectively, and we investigated the protective effects of wild type and mutant Tat-$\alpha$-synucleins in vitro and in vivo. WT Tat-$\alpha$-synuclein rapidly transduced into an astrocyte cells and protected the cells against paraquat induced cell death. However, mutant Tat-$\alpha$-synucleins did not protect at all. In the mice models exposed to the herbicide paraquat, the WT Tat-$\alpha$-synuclein completely protected against dopaminergic neuronal cell death, whereas mutants failed in protecting against oxidative stress. We found that these protective effects were characterized by increasing the expression level of heat shock protein 70 (HSP70) in the neuronal cells and this expression level was dependent on the concentration of transduced WT Tat-$\alpha$-synuclein. These results suggest that transduced Tat-$\alpha$-synuclein might protect cell death from oxidative stress by increasing the expression level of HSP70 in vitro and in vivo and this may be of potential therapeutic benefit in the pathogenesis of PD.

• Journal of Internet of Things and Convergence
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• v.7 no.4
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• pp.51-58
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• 2021

This study is a quasi-experimental study designed to examine the effects of color therapy on job stress and depression by applying color therapy to intensive care unit nurses. The subjects of this study were S hospital located in S city, a secondary medical institution with 500 beds, P hospital located in B city, and nurses in the intensive care unit of two general hospitals. The data collection period was 8 weeks from November 2, 2020 to December 25, 2020, with 29 patients in the experimental group and 29 in the control group. The data were analyzed by chi-square test, independent t-test and paired t-test using the SPSS WIN 22.0 program. The experimental group applied color therapy twice a day (before and after work) using a standardized canvas frame painted in yellow, red, blue, and three colors, and a total of 20 times for 10 days, and the control group lived and woked as usual without appiled color therapy. As a result of study, the experimental group showed a significant decrease in job stress score by 0.43 points and depression score by 0.26 points compared to the control group