• Journal of Life Science
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• v.33 no.1
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• pp.102-113
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• 2023

This review discusses the cellular and molecular mechanisms by which the endometrial estrogen and progesterone receptors regulate local estrogen production, expression of the specific estrogen receptors, progesterone resistance, inflammatory responses and the differentiation and survival of endometriotic cells in endometrial inflammation. The epigenetic aberrations of endometrial stromal cells play an important role in the pathogenesis and progression of endometriosis. In particular, differential methylation of the estrogen receptor genes changes in the stromal cells the dominancy of estrogen receptor from ERα into ERβ, and results in the abnormal estrogen responses including inflammation, progesterone resistance and the disturbance of retinoid synthesis. These stromal cells also stimulate local estrogen production in response to PGE2 and the SF-1 mediated induction of steroidogenic enzyme expression, and the increased estradiol then feeds back into the ERβ to repeat the vicious inflammatory cycle through the activation of COX-2. In addition, high levels of ERβ expression may also change the chromatin structure of endometrial mesenchymal stem cells, and together with the repeated menstrual cycles can induce formation of the endometriotic tissue. The cascade of these serial events then leads to cell adhesion, angiogenesis and survival of the differentiation-disregulated stromal cells through the action of inflammatory factors such as ERβ-mediated estrogen, TNF-α and TGF-β1. Therefore, understanding of the dynamic hormonal changes during the menstrual cycle and the corresponding signal transduction mechanisms of the related nuclear receptors in endometrium would provide new insights for treating inflammatory diseases such as the endometriosis.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.4
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• pp.33-44
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• 2023

Wind power is one of the most efficient and reliable energy sources in the transition to a low-carbon society. In particular, offshore wind power provides a high-quality and stable wind resource compared to onshore wind power while both present a higher installed capacity than other renewables. In this paper, we present our new program, the X-WIND program well suitable for the assessment of the substructure of offshore wind turbines. We have developed this program to increase the usability of analysis programs for offshore wind energy substructures by addressing the shortcomings of existing programs. Unlike the existing programs which cannot solely perform the substructure analyses or lack pre-post processors, our X-WIND program can complete the assessment analysis for the offshore wind turbines alone. The X-WIND program is embedded in AutoCAD so that both design and analysis are performed on a single platform. This also performs static and dynamic analysis for wind, wave, and current loads, essential for offshore wind power structures, and includes pre/post processors for designs, mesh developments, graph plotting, and code checking. With this expertise, our program enhances the usability of analysis programs for offshore wind energy substructures, promoting convenience and efficiency.

• Journal of The Korean Association For Science Education
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• v.43 no.4
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• pp.351-368
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• 2023

The scientist-led Research and Education (R&E) program aims to strengthen gifted science students' research capabilities under the guidance of scientists. Students' actual research experiences in scientist-led R&E activities range from understanding how scientists conduct research to actively participating in research. To develop R&E that promotes student agency, i.e., student participation, this study aimed to identify the pedagogical characteristics that supported gifted science students' agentic participation in the scientist-led R&E program. We conducted interviews with learners and scientists in three teams undertaking R&E activities every three months. The interview covered their perceptions of R&E activities, student participation, and scientists' support for the activities. The recordings and transcripts of the interviews were used as primary data sources for the analysis. The trajectory of each team's activities, as well as the learners' and scientists' dynamic positioning were identified. Based on this analysis, we inductively identified the pedagogical characteristics that emerged from classes in which the scientists supported the students' learning and engagement in research. Regarding agency, three types of student participation were identified: 1) the sustained exercise of agency, 2) the initial exercise and subsequent discouragement of agency, and 3) the continuous non-exercise of agency. Two pedagogical characteristics that supported the learners' agentic participation were identified: 1) opportunities for students to take part in research management and 2) scientist-student interactions encouraging learners to present expert-level ideas. This study contributes to developing pedagogies that foster gifted science students' agentic participation in scientist-led R&E activities.

• Analytical Science and Technology
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• v.19 no.1
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• pp.107-114
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• 2006

Early diagnosis and medical intervention are critical for the treatment of patients with metabolic disorders. A rapid analytical method was developed for simultaneous quantification of organic acids and amino acids in urine without labor-intensive pre-extraction procedure showing high sensitivity and specificity. A new method consisted of simple two-step trimethylsilyl (TMS)-trifluoroacetyl (TFA) derivatization using GC/MS-selective ion monitoring (SIM). Filter paper urine specimens were dried under nitrogen after being fortified with internal standard (tropate) in a mixture of distilled water and methanol. Methyl orange was added to the residue as indicator reagent. Silyl derivative of carboxylic functional group was followed by trifluoroacetyl derivative for amino functional group. N-methyl-N-(trimethylsilyl-trifluoroacetamide) and N-methyl-bistrifluoroacetamide were consecutively added and heated for 15-20 min at $65^{\circ}C-70^{\circ}C$, for TMS-TFA derivative, respectively. This reactant was analyzed by GC/MS-SIM. Linear dynamic range showed 0.001-50 mg with the detection limit of (S/N=3) 10-200 ng, and the quantification limit of 80-900 ng in urine. Correlation coefficient of regression line was 0.994-0.998. When the method was applied to the patients 'urine, it clearly differentiated the normal from the patient with metabolic disorder. The study showed that the developed method could be the method of choices in rapid and sensitive screening for organic aciduria and amino acidopathy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2C
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• pp.73-80
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• 2006

The shear behavior of four different interfaces consisting of four types of geosynthetics was investigated, and both static and dynamic test for the geosynthetic interfaces were conducted. The monotonic shear experiments were performed by using an inclined board apparatus and large direct shear device. The interface shear strength obtained from the inclined board test was compared with calculated values from large direct shear tests. The comparison results indicated that direct shear tests show high possibility to over-predict the shear strength in the low normal stress range where direct shear tests are not performed. Curved failure envelopes were also obtained for interface cases where two static shear tests were conducted. By comparing the friction angles measured from three tests, i.e. direct shear, inclined board, and shaking table test, it was found that the friction angle might be different depending on the test method and normal stresses applied in the research. Therefore, it was concluded that the testing method should be determined carefully by considering the type of loads and the normal stress expected in the field with using the geosynthetic materials installed in the site.

• (The) Research of the performance art and culture
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• no.39
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• pp.863-901
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• 2019

This paper deals with the process of developing a traditional culture content based on the historical spread of Jajimu, an ethnic dance of ancient Tashkent(Chach), to Tang China and then to Goryeo in Korean peninsula. Jajimu as a solo dance form was a very enegetic dance form that reflects the dynamic nature of namadic life, and it enjoyed high popularity in Tang China due to its exotic style after the 8th century A.D. Later, it gave a birth to a derivative duet dance form called Ssangjaji or Guljaji, an highly sophisticated elegant court dance item that reflects the aesthetic taste of Tang China. Further, the Ssangjaji was flowed into Georyeo around in the 11th century or earlier, and was transformed into a Korean court dance while renaming it as Yeonhwadae that means 'lotus pedestal'. I tried the production of a special performance which displys those three dance forms on same stage to demonstrate the historical connection of ancient Asian dance. It was not easy to restore the music, dance and costume of Jajimu and Ssangjaji because of limited historical materials whereas those of Korean Yeonhwadae have been well preserved and transmitted owing to old dance and music notation system. A large amount of audio, visual materials were collected and analysed to overcome those limits, and its result was utilized efficiently for the production. The final performance was the culmination of long preparation process for 11 months in 2015. In spite of some limits, this project has a historical meaning in the point that it was the first trial of same kind in the world.

• Asia Marketing Journal
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• v.10 no.1
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• pp.95-131
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• 2008

This study serves the main research purpose of verifying the hypothetical relationship between antecedent and consequence variables of shopping experience based on the classification system by Schmitt (1999) who dimensionalized experience into five components (sense, feel, think, act, relate). Specifically, the study seeks to fulfill the following three research objectives. First, it substantiates dynamic relationships among the five experiential components comprising the strategic experiential modules that serve as the basis of the theoretical framework of the study. Especially, it focuses on interactive relationships among the experiential components by taking a holistic view of the experience. Second, the study seeks to uncover the effects of pre-experiential antecedents such as shopping motivation and shopping involvement, based on taxonomy of motivation as product-centered vs. experience-centered. Third, the study investigates the effects of shopping experience on intention to revisit with regard to department store, discount store, and Internet shops, based on customers' store experiences. The major findings from this study are as follows: first, the five experiential components were found to have a high level of correlations according to hypothesis verification. Second, shopping motivation was learned to have significant effects on preference toward thinking as well as feeling experiences. That is, product-centered (vs. experience-centered) shopping motivation exerted a greater influence on cognitive (vs. affective experience than affective (vs. cognitive) experience.

• Journal of Environmental Impact Assessment
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• v.32 no.5
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• pp.318-337
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• 2023

This study utilizes system dynamics to examine the effects of fine dust reduction policies on PM10 concentration and health. System dynamics has the advantage of modeling the dynamic and circular relationship between PM₁₀ emission sources, reduction policies, PM₁₀ concentration, and health effect. The study created policy scenarios for Korea's representative fine dust reduction policies - industrial PM₁₀ emission control, diesel vehicle regulation, expansion of electric vehicles, and expansion of parks and green areas - and compared the results with the 2030 baseline if the current trend is maintained. The analysis showed that the policy of supporting electric vehicles reduced PM₁₀ concentration by 0.21 ㎍/m³ and reduced the number of people with circulatory diseases by 494, and the effect was evenly distributed across the country. The industrial emissions regulation scenario resulted in the highest PM₁₀ concentration reduction of 0.22 ㎍/m³, but had a lower reduction in the number of people affected (358) than the EV support strategy, which could be attributed to the fact that this policy had a particularly high PM₁₀ reduction effect in industrial areas such as Danyang-gun, Chungcheongbuk-do, and Sahagu, Busan. As a policy implication, this study suggests that it is necessary to apply fine dust policies tailored to the characteristics of local emission sources.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.6
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• pp.454-464
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• 2023

This paper proposes a low-power 8-bit asynchronous SAR ADC with a sampling rate of 1 MS/s for sensor node applications. The ADC uses bootstrapped switches to improve linearity and applies a VCM-based CDAC switching technique to reduce the power consumption and area of the DAC. Conventional synchronous SAR ADCs that operate in synchronization with an external clock suffer from high power consumption due to the use of a clock faster than the sampling rate, which can be overcome by using an asynchronous SAR ADC structure that handles internal comparisons in an asynchronous manner. In addition, the SAR logic is designed using dynamic logic circuits to reduce the large digital power consumption that occurs in low resolution ADC designs. The proposed ADC was simulated in a 180-nm CMOS process, and at a 1.8 V supply voltage and a sampling rate of 1 MS/s, it consumed 46.06 𝜇W of power, achieved an SNDR of 49.76 dB and an ENOB of 7.9738 bits, and obtained a FoM of 183.2 fJ/conv-step. The simulated DNL and INL are +0.186/-0.157 LSB and +0.111/-0.169 LSB.

• Smart Media Journal
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• v.13 no.3
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• pp.18-26
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• 2024

Road surface monitoring is essential for maintaining road environment safety through managing risk factors like rutting and crack detection. Using autonomous driving-based UGVs with high-performance 2D laser sensors enables more precise measurements. However, the increased energy consumption of these sensors is limited by constrained battery capacity. In this paper, we propose a fusion sensor system for efficient surface monitoring with UGVs. The proposed system combines color information from cameras and depth information from line laser sensors to accurately detect surface displacement. Furthermore, a dynamic sampling algorithm is applied to control the scanning frequency of line laser sensors based on the detection status of monitoring targets using camera sensors, reducing unnecessary energy consumption. A power consumption model of the fusion sensor system analyzes its energy efficiency considering various crack distributions and sensor characteristics in different mission environments. Performance analysis demonstrates that setting the power consumption of the line laser sensor to twice that of the saving state when in the active state increases power consumption efficiency by 13.3% compared to fixed sampling under the condition of λ=10, µ=10.