• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.34.2-35
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• 2018

Galaxy transition from star-forming to quiescent, accompanied with morphology transformation, is one of the key unresolved issues in extragalactic astronomy. Although several environmental mechanisms have been proposed, a deeper understanding of the impact of environment on galaxy transition still requires much exploration. My Ph.D. thesis focuses on which environmental mechanisms are primarily responsible for galaxy transition in different environments and looks at what happens during the transition phase using multi-wavelength photometric/spectroscopic data, from UV to mid-infrared (MIR), derived from several large surveys (GALEX, SDSS, and WISE) and our GMOS-North IFU observations. Our multi-wavelength approach provides new insights into the *late* stages of galaxy transition with a definition of the MIR green valley different from the optical green valley. I will present highlights from three areas in my thesis. First, through an in-depth study of environmental dependence of various properties of galaxies in a nearby supercluster A2199 (Lee et al. 2015), we found that the star formation of galaxies is quenched before the galaxies enter the MIR green valley, which is driven mainly by strangulation. Then, the morphological transformation from late- to early-type galaxies occurs in the MIR green valley. The main environmental mechanisms for the morphological transformation are galaxy-galaxy mergers and interactions that are likely to happen in high-density regions such as galaxy groups/clusters. After the transformation, early-type MIR green valley galaxies keep the memory of their last star formation for several Gyr until they move on to the next stage for completely quiescent galaxies. Second, compact groups (CGs) of galaxies are the most favorable environments for galaxy interactions. We studied MIR properties of galaxies in CGs and their environmental dependence (Lee et al. 2017), using a sample of 670 CGs identified using a friends-of-friends algorithms. We found that MIR [3.4]-[12] colors of CG galaxies are, on average, bluer than those of cluster galaxies. As CGs are located in denser regions, they tend to have larger early-type galaxy fractions and bluer MIR color galaxies. These trends can also be seen for neighboring galaxies around CGs. However, CG members always have larger early-type fractions and bluer MIR colors than their neighboring galaxies. These results suggest that galaxy evolution is faster in CGs than in other environments and that CGs are likely to be the best place for pre-processing. Third, post-starburst galaxies (PSBs) are an ideal laboratory to investigate the details of the transition phase. Their spectra reveal a phase of vigorous star formation activity, which is abruptly ended within the last 1 Gyr. Numerical simulations predict that the starburst, and thus the current A-type stellar population, should be localized within the galaxy's center (< kpc). Yet our GMOS IFU observations show otherwise; all five PSBs in our sample have Hdelta absorption line profiles that extend well beyond the central kpc. Most interestingly, we found a negative correlation between the Hdelta gradient slopes and the fractions of the stellar mass produced during the starburst, suggesting that stronger starbursts are more centrally-concentrated. I will discuss the results in relation with the origin of PSBs.

• Journal of The Korean Association For Science Education
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• v.33 no.4
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• pp.763-777
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• 2013

This is a case study on two schools practising integrated science education (hereafter ISE). The purposes of this study are to investigate the types and features of ISE in the schools actively practising ISE, to identify the contextual factors of the schools, and to give implications for implementing ISE in schools. This study investigated the contextual factors in practicing ISE with a focus on the two schools, a middle school in Gyeonggi-do and a high school in Busan. They were breaking down the boundaries among teaching subjects and providing student-oriented instruction with problems in the real world. The data were collected by observing classes, by interviewing teachers, and by reviewing school documents and students' reports. The research findings are as follows: first, the two schools took part in ISE actively. They teach science to students providing integrated experiences mainly by using interdisciplinary knowledge and/or by solving the problems pertaining to the real world. While the former integrated subjects centering on topics, the latter focused on a project-based learning driven by students. They have differences in regard to the role of teachers and students, the level of integration and the type of integration. Second, the contextual factors that enabled ISE to be implemented there were found. The previous studies revealed six contextual factors in practising ISE: small and stable learning environment, leadership, team activities, in-school planning time, flexible timetable and community links. This study also found similar factors. However, the cases of this study provided ISE on a large scale and in a short period of time, instead of a small and stable learning environment. Teachers viewed the process of ISE not only as a tool to overcome the conservative culture of teachers but also as a pursuit of innovation.

• Journal of the Korean Home Economics Association
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• v.46 no.9
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• pp.99-112
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• 2008

The increasing rate of obesity in school aged children has become a conspicuous social phenomenon in Korea. This has been linked to greater economic growth, increasingly westernized dietary habits, and a consumer driven society. Given that obesity can lead to social exclusion or unfavorable attention by other students in a school setting, the design of plus-size garments have become important for effective appearance management skills. This research aimed to establish a somatotype database for obese school boys, aged 10 to 12, in order to develop a sizing system for plus-size upper garments. In order to measure somatotype of average and obese school boys, five categories were recorded; height, obesity, length of trunk, thickness of neck and chest. For obese boys, subcutaneous fat thickness and position of B.P/shoulder point factors were recorded. Obesity factor was subdivided into overall and specific ones, and while the deviation of obese body types was severe compared to the average type. Obese body type showed significantly higher measurements in width, girth, thickness. This is linked to the fact that the frequency ratio of obesity increases with age. Stature and chest were chosen as control dimensions for boys' wear. As crosstabulation of stature(5cm interval) and chest girth(2, 3 and 4cm), and stature(5cm interval)/chest girth(3cm interval) sizing system showed, the most effective cover ratio and adaptability to the data distribution $25{\sim}75$ quartile. Based on the findings, 10 sizes were formulated for average body type, while 18 sizes were formulated for obese type, whose size cover ratios were 48% and 62.9%, respectively. The primary ranges of stature were $145cm{\sim}150cm$, while those of chest girth were $79{\sim}82cm$. Each size was declared as "chest-somatotype{A(average)/O(obesity)-stature". This study proposed a plus-size upper garment sizing systems for obese boys, accompanied with reference measurements for suit, casual wear and underwear. The finding showed that the two systems were totally separate and not overlapping, meaning that plus-size sizing system is essential for obese school boys. The obesity type system had more size and wider range specs.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.11-15
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• 2016

Gastrointestinal cancers remain the most prevalent cancers in many developing countries such as Iran. The aim of this study was to estimate incidence, prevalence and mortality, as well as time trends for gastrointestinal cancers in Isfahan province of Iran for the period 2001 to 2010 and to project these estimates to the year 2020. Estimates were driven by applying the MIAMOD method (a backward calculation approach using mortality and relative survival rates). Mortality data were obtained from the Ministry of Health and the relative survival rate for all gastrointestinal cancers combined was derived from the Eurocare 3 study. Results indicated that there were clear upward trends in age adjusted incidence (males 22.9 to 74.2 and females 14.9 to 44.2), prevalence (males 52.6 to 177.7 and females 38.3 to 111.03), and mortality (males 14.6 to 47.2 and females 9.6 to 28.2) rates per 100,000 for the period of 2001 to 2010 and this upward state would persist for the projected period. For the entire period, the male to female ratio increased slightly for all parameters (incidence rate increased from 1.5 to 1.7, prevalence from 1.4 to 1.6, and mortality from 1.5 to 1.7). In males, totals of 2,179 incident cases, 5,097 prevalent cases and 1,398 mortality cases were predicated to occur during the study period. For females the predicted figures were 1,379, 3,190 and 891, respectively. It was concluded that the upward trend of incidence alongside increase in survival rates would induce a high burden on the health care infrastructure in the province of Isfahan in the future.

• The Journal of the Acoustical Society of Korea
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• v.19 no.1
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• pp.16-24
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• 2000

In this paper the performance of a closed-loop power control scheme using variable step size decision method for DS/CDMA based-low earth orbit(LEO) mobile satellite systems in which the long round trip delay is a dominant performance degradation factor is evaluated. Because there are fundamental differences in the characteristics between the LEO mobile satellite channel and terrestrial mobile channel, such as long round trip delay and different elevation angle, these factors are considered in channel modeling based on the European Space Agency(ESA) measurement data. Since the round trip delay (from the mobile terminal to the gateway station via satellite) is typically 10∼20ms in low altitude satellite channels, closed-loop power control is much less effective than it is on a terrestrial channel. Thus, the adaptive power control scheme using a variable step size control is essential for overcoming the long round trip delay and fading due to the elevation angle. It is shown that the standard deviation of signal to interference ratio(SIR) adopting a variable step size closed-loop power control scheme is much less than that of a fixed step size closed-loop power control. Furthermore, we have driven the conclusion that the measurement interval of power control commands is optimal choice when it is twice the round trip delay.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.6
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• pp.203-213
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• 2015

This study is to test the influence of safety management activities and employees' safety awareness on safety behavior in the construction company following the atmosphere of a safety-driven society. Recently, the perspective of many individuals and companies for safety management is changing and the recognition is spreading that physical and conscious investment on the safety of industrial sites are not an useless cost but the vital element to enhance the corporate competitiveness. CEOs have an emphasis on the safety management in their workplace as a top priority. For this study, the data were collected and analyzed from 300 employees of industrial sites. Firstly, the results showed that safety management activities and employees' safety awareness had a positive impact on organizational trust. Secondly, the organizational trust had a positive impact on safety behavior. Thirdly, safety management activities and employees' safety awareness had a positive impact on safety behavior. And also found out the organizational trust had the mediating role between safety management activities and safety behavior, and between employees' safety awareness and safety behavior. The results of this study suggested that safety management activities and employees' safety awareness in the construction companies are very important factors influencing on the safety behavior, and the investment for the safety of the construction company should be continued.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.437-443
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• 2003

Epidemiological data suggest that lycopene has anticancer activities in humans. Insulin-like growth factor-I receptor (IGF-IR) is a transmembrane tyrosine kinase that mediates the biological actions of IGFs and may play an active role in cancer progression. Because our previous in vitro studies have indicated lycopene inhibits HT-29 cell growth, the aim of this study was to determine whether lycopene induces apoptotic cell death and the inhibitory effect of lycopene on HT-29 cell growth is related to changes in IGF-IR levels and the receptor's intracellular signalling pathways. HT-29 cells were incubated for 4 days in serum-free medium in the presence of 0, 25, 50, or 100 $\mu$M lycopene, and the DNA fragmentation assay was performed. Cells treated with lycopene produced a distinct oligonucleosomal ladder with different sizes of DNA fragments, a typical characteristic of cells undergoing apoptosis. HT-29 cells were cultured for 4 days in serum-free medium in the presence of 0~100 $\mu$M lycopene and IGF-I (10nM) was added for 0~60 minutes immediately prior to lysate preparations. Western blot analysis of total lysates revealed that lycopene decreased the levels of IRS-1, Akt, phosphatidylinositol 3-kinase (PI3K), and IGF-IR $\beta$-subunit, and increased the levels of the IGF-IR precursor dose dependently. Lycopene also decreased IGF-I-induced phosphorylation of IGF-IR$\beta$, IRS-1 and Akt, which were, at least in part, due to decreased expression of these proteins. These results suggest that lycopene induces apoptosis of HT-29 cells by inhibiting IGF-IR signaling thereby interfering with an IGF-II-driven autocrine growth loop, which is known to exist in this cell line.

• Journal of Distribution Science
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• v.13 no.10
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• pp.83-91
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• 2015

Purpose - The purpose of this study is to identify whether the operation of cultural centers in discount stores contributes to their profitability. Thus, this study is aimed at exploring how the lifestyles of customers who use the cultural centers influence their intention to use the discount stores. Specifically, the effect of shopping value on the correlation between the lifestyle types and usage intention of the customers were examined through a structured research model. To verify the effect, a survey on 139 customers of the Cultural Center of Nonghyup Hanaro Club's S branch was conducted and the valid questionnaires were used for analysis. Research design, data, and methodology - The findings are as follows. First, the lifestyles seeking self-realization had a positive effect on utilitarian value, and lifestyles seeking pop cultures had a positive effect on hedonic value. Second, the mediating effect of shopping value on the correlation between the lifestyle types and usage intention of the customers is as follows. Utilitarian value had a mediating effect only on the lifestyles seeking self-realization. In case of lifestyles seeking pop cultures, the use of Cultural Center had no effect on the intention to use the discount store. Third, an analysis of a revised research model revealed that the store usage intention of lifestyles seeking pop cultures can be enhanced by boosting the utilitarian value through hedonic value. Results - The findings suggest the following. Customers with lifestyles seeking self-realization, who value what is beneficial to them with little attention to the perceptions of others, are highly interested in the benefits they can gain from shopping. As for customers with lifestyles seeking pop cultures, they are highly likely to consume products popular in a particular culture such as new products and sports, based on financial stability they pursue. Thus, they prefer more subjective, personal experience, unlike consumers pursuing utilitarian value. Conclusions - As a result, the former pursues hedonic value gained in the process of shopping with fun and joy, rather than doing shopping with a particular purpose in mind. Therefore, Cultural Centers need to offer information that fits the lifestyles of the users so that they are more likely to use the discount stores. However, if the Cultural Centers offer unified, profit-driven products and information, just to increase their store sales, it can backfire, which occurred in the past. On the other hand, if they provide information that fits the lifestyles of the users, it can actually increase the sales. Also, the findings suggest that sophisticated marketing strategies that can boost the hedonic value of customers by linking the educational contents of Cultural Centers to actual shopping, which is beneficial to consumers, should be set and operated by discount stores. In particular, customers with lifestyles seeking self-realization can be encouraged to use the stores by making them recognize the utilitarian value. However, the use of Cultural Centers doesn't necessarily lead to higher sales among customers with lifestyles seeking pop cultures. As mentioned previously, unified marketing strategy is not as effective for Cultural Centers of large discount stores.

• Molecules and Cells
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• v.28 no.4
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• pp.383-388
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• 2009

The dehydration responsive element binding protein 2C (DREB2C) is a dehydration responsive element/C-repeat (DRE/CRT)-motif binding transcription factor that induced by mild heat stress. Previous experiments established that overexpression of DREB2C cDNA driven by the cauliflower mosaic virus 35S promoter (35S:DREB2C) resulted in increased heat tolerance in Arabidopsis. We first analyzed the proteomic profiles in wild-type and 35S:DREB2C plants at a normal temperature ($22^{\circ}C$), but could not detect any differences between the proteomes of wild-type and 35S: DREB2C plants. The transcript level of DREB2C in 35S: DREB2C plants after treatment with mild heat stress was increased more than two times compared with expression in 35S:DREB2C plants under unstressed condition. A proteomic approach was used to decipher the molecular mechanisms underlying thermotolerance in 35S:DREB2C Arabidopsis plants. Eleven protein spots were identified as being differentially regulated in 35S:DREB2C plants. Moreover, in silico motif analysis showed that peptidyl-prolyl isomerase ROC4, glutathione transferase 8, pyridoxal biosynthesis protein PDX1, and elongation factor Tu contained one or more DRE/CRT motifs. To our knowledge, this study is the first to identify possible targets of DREB2C transcription factors at the protein level. The proteomic results were in agreement with transcriptional data.

• Journal of Korean Society of Transportation
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• v.35 no.6
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• pp.545-556
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• 2017

Various assessment indexes have been developed and utilized to evaluate the driver workload. However, existing workload assessment indexes do not fully reflect driving habits and driving patterns of individual drivers. In addition, there exists significant differences in the amount of workload experienced by a driver and the ability to overcome the driver's workload. To overcome these limitations associated with existing indexes, this study has developed a novel workload assessment index to reflect an individual driver's driving pattern. An average of the absolute values of the steering velocity for each driver are set as a threshold value in order to reflect the driving patterns of individual drivers. Further, the sum of the areas of the steering velocities exceeding the threshold value, which is defined as erratic steering area (ESA) in this study, was quantified. The developed ESA index is applied in evaluating the driver workload of manually driven vehicles in automated vehicle platooning environments. Driving simulation experiments are conducted to collect drivers' responsive behavior data which are used for exploring the relationship between the NASA-TLX score and the ESA by the correlation analysis. As a result, ESA is found to have the greatest correlation with the NASA-TLX score among the various driver workload evaluation indexes in the lane change scenario, confirming the usefulness of ESA.