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The Making of a Science Town: The Case of Daedeok, Korea (과학도시의 생성과 발전: 대덕연구단지의 경우)

  • Kim, Ho-Yeon
    • Journal of the Economic Geographical Society of Korea
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    • v.12 no.1
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    • pp.83-95
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    • 2009
  • This paper provides a general overview and critical assessment of Daedeok Science Town (DST) in Korea, mainly through the lens of the related literature. DST symbolizes the government-led creation of a new science town and represents a bold attempt to consolidate national R&D efforts in a designated area with a view to supplying basic scientific knowledge to industries nationwide. It has achieved considerable success by improving the research environment and promoting venture spin-offs and network formation. However, while DST has played a pivotal role in ushering in the era of the knowledge-based economy, new measures are required for it to remain viable. To this end, efforts should be made to direct government support toward new firm establishment, finance, and tighter networking. DST also needs to host large corporations in the area as these could both act as a market for venture businesses and serve as providers of funds.

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Inhibition of Rat Lense Aldose Reductase by Flavonoids from Dandelions

  • Mok, So-Youn;Lee, Sul-Lim;Kim, Hye-Min;Lee, Jeong-Min;Lee, Dong-Gu;Ahn, Young-Hee;Park, Chun-Geon;Cho, Eun-Ju;Lee, Sang-Hyun
    • Natural Product Sciences
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    • v.17 no.2
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    • pp.130-134
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    • 2011
  • The purpose of this study was to evaluate the therapeutic potential of naturally occurring aldose reductase (AR) inhibitors isolated from Korean native plants. The MeOH extract and stepwise polarity fractions of dandelions were tested on rat lens AR inhibition in vitro. Of these, the EtOAc fractions from the leaves of dandelions (Traxacum coreanum, T. officinale, and T. ohwianum) exhibited an AR inhibitory activity ($IC_{50}$ values, 2.37, 1.73 and 2.68 ${\mu}g/ml$, respectively). A chromatography of the EtOAc fraction from the leaves of T. coreanum led to the further isolation of two flavonoids identified as luteolin and luteolin 7-O-glucopyranoside. These compounds exhibited strong AR inhibitory activity, with $IC_{50}$ values of 0.15 and 1.05 ${\mu}M$, respectively. These results suggested that luteolin is a potent AR inhibitor within dandelions and that it could be a useful lead compound in the development of a novel AR inhibitory agent against diabetic complications.

Movie Popularity Classification Based on Support Vector Machine Combined with Social Network Analysis

  • Dorjmaa, Tserendulam;Shin, Taeksoo
    • Journal of Information Technology Services
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    • v.16 no.3
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    • pp.167-183
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    • 2017
  • The rapid growth of information technology and mobile service platforms, i.e., internet, google, and facebook, etc. has led the abundance of data. Due to this environment, the world is now facing a revolution in the process that data is searched, collected, stored, and shared. Abundance of data gives us several opportunities to knowledge discovery and data mining techniques. In recent years, data mining methods as a solution to discovery and extraction of available knowledge in database has been more popular in e-commerce service fields such as, in particular, movie recommendation. However, most of the classification approaches for predicting the movie popularity have used only several types of information of the movie such as actor, director, rating score, language and countries etc. In this study, we propose a classification-based support vector machine (SVM) model for predicting the movie popularity based on movie's genre data and social network data. Social network analysis (SNA) is used for improving the classification accuracy. This study builds the movies' network (one mode network) based on initial data which is a two mode network as user-to-movie network. For the proposed method we computed degree centrality, betweenness centrality, closeness centrality, and eigenvector centrality as centrality measures in movie's network. Those four centrality values and movies' genre data were used to classify the movie popularity in this study. The logistic regression, neural network, $na{\ddot{i}}ve$ Bayes classifier, and decision tree as benchmarking models for movie popularity classification were also used for comparison with the performance of our proposed model. To assess the classifier's performance accuracy this study used MovieLens data as an open database. Our empirical results indicate that our proposed model with movie's genre and centrality data has by approximately 0% higher accuracy than other classification models with only movie's genre data. The implications of our results show that our proposed model can be used for improving movie popularity classification accuracy.

'Look at the Alcohol If You Want to Know the Country': Drinking Vessels as a Cultural Marker of Medieval Korea

  • KIM HAN, IN-SUNG
    • Acta Via Serica
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    • v.4 no.2
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    • pp.29-59
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    • 2019
  • As 'a total social fact,' drinks and drinking may serve as a lens through which we can view a distant society. Although not frequently discussed, drinking vessels serve the same function for accessing a past world hidden or forgotten behind written records. The present article is an art history attempt to seek a cultural link between liquor vessels used in medieval Korea and the political and social change of the period. The Goryeo period (918-1392) saw an unprecedented abundance of drinking vessels in various forms and decorations. Goryeo artisans and craftsmen produced ewers, pitchers, flasks, bottles, and others in addition to the pre-existing shapes of vessels mainly consisting of jars and bowls. I argue that this sudden burst of creativity during the Goryeo period was closely related to Goryeo's constant and diverse contacts with foreign powers. Their zone of international connections was not confined to the Chinese world, as we have commonly presumed. Even before the Mongol intervention, Goryeo was in contact with regions beyond East Asia through the northern nomadic states. Khitan Liao was recorded as having worked as a kind of international intermediary to link the Chinese and Islamic worlds. This medieval global culture became a norm in Goryeo society when it became an important part of the Mongol Empire. These nomadic powers brought global trends to Goryeo, and foreign drinks were among them; kumis, araq, and grape wines are just three cases of them discussed in this article. The change of alcoholic drinks led to, or was accompanied by, a new range of drinking vessels. Three types of ewers, familiar to East Asian consumers but foreign in their origin, are discussed in the main text to highlight such social change. Three more cases of drinking cups are also presented. The article shows that medieval Korean society was far more open to international art and culture than our usual understanding, and in their drinking vessels, Goryeo culture embraced global trends reaching China, the Islamic world and Europe.

Development of Portable Laryngeal Stroboscope (휴대형 후두 스트로보스콥의 개발)

  • Lee, Jae-Woo;Kwon, Soon-Bok;Lee, Byung-Joo;Lee, Jin-Choon;Goh, Eui-Kyung;Chon, Kyong-Myong;Wang, Soo-Geun;Ro, Jung-Hoon
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.17 no.1
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    • pp.28-37
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    • 2006
  • Purpose: Evaluation of vocal cord vibration is very important in cases of voice disorders. There are several equipments for examining the vocal fold vibration such as laryngeal stroboscope, ultra high-speed digital imaging system, and videokymograph. Among these, laryngeal stroboscope is the most popular equipment because of easy to examine the laryngeal pathology. However, current laryngo-stroboscopes are too bulky to move and relatively expensive. The purpose of this research is to develope a portable laryngeal stroboscope of equivalent performance with the current equipments. Methods and Materials: Recently developed high luminescent white LEDs(light emitting diodes) are placed at the head of the endoscope as light sources for the CCD image sensor which is also placed at the head with imaging lens. This arrangement eliminates the bulky light source like expensive halogen or xenon lamps as well as the optical light guiding cables. The LEDs are controlled to flash in phase with the voice frequency of the examinee. The CCD captures these strobo images and converts them into video signals for examinations. Results: There was no functional differences between preexisting stroboscope and the newly developed stroboscope of this study. LED light sources and microprocessor based control circuits of the stroboscope enabled the development of flicker-less, hand-held, portable and battery-operating stroboscope. Conclusion: The developed stroboscope is cost-effective, small-sized, easy to use and very easy desirable to bring and to use in any place.

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The Cinereous Vulture, Aegypius monachus: Cannibalism in its Wintering Ground (월동지에서 독수리(Aegypius monachus)의 카니발리즘)

  • Kang, Seung Gu
    • Korean Journal of Environment and Ecology
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    • v.32 no.3
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    • pp.256-260
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    • 2018
  • Cannibalism is a widely observed phenomenon in the animal kingdom. However, it is rarely found among birds outside nests in the wild because it occurs irregularly and it is almost impossible to monitor animal behavior constantly. On 17 January 2017, this behavior was directly observed from a group of vultures feeding on a conspecific in a paddy field near Lake Geumho in Haenam-gun ($34^{\circ}35^{\prime}58.25^{{\prime}{\prime}}N$, $126^{\circ}26^{\prime}57.64^{{\prime}{\prime}}E$). It was observed and recorded with the binoculars and a camera with a telephoto lens in a car approximately 20 m (or 60 m) away from the site. The observer approached the feeding site after the last vulture had finished feeding and flown away and found remains of a vulture, including body feathers, skull, sterna keel, and both legs. It was the first report of cannibalism in Cinereous vulture Aegypius monachus in its overwintering grounds. The remaining skeleton was very fleshy, and the surrounding grass was wet with the blood of vulture. No other traces of a mammal or bird that could have been the vultures' prey were found. This report provides a detailed account of the events related to this rare observation and the causes that might have led to it.

Key Stages of a Research and Students' Epistemic Agency in a Student-Driven R&E (학생 주도의 R&E 활동에서 드러나는 연구 활동의 주요 단계 및 학생의 인식적 행위주체성)

  • Lee, Minjoo;Kim, Heui-Baik
    • Journal of The Korean Association For Science Education
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    • v.39 no.4
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    • pp.511-523
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    • 2019
  • In this age of the $4^{th}$ industrial revolution, we, science educators, are giving more light on students' agentic behavior in the process of educating future scientist. This study, with the analytic lens of epistemic agency, explores the key stages of a student-driven R&E program rather than the scientist-led R&E program. It also examines to understand the emergence of students' epistemic agency in each stage of R&E. Data from participant observation for 18 months and in-depth interviews were collected and analyzed with the constant comparative method of grounded theory. This study identifies and describes five key stages of student-driven R&E: The stage of exploring research theme, designing research, performing lab activity, interpreting results, and communicating research. It also finds that (a) students' epistemic agency emerged with the constant interactions with the R&E structure; (b) students' epistemic agency has deep relations with the epistemic beliefs of the students; (c) students positioned themselves as decision-makers in the R&E practice; (d) the redistributed power and authority of the R&E contributed to the emergence of students' epistemic agency.

The Anthropocene and the Humanities - Future of the Earth and the Humanities Envisioned by the Ecofeminism of Carolyn Merchant's (인류세와 인문학 -캐롤린 머천트의 생태 페미니즘이 조망하는 지구와 인문학의 미래)

  • Lee, Yun-Jong
    • Journal of Popular Narrative
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    • v.27 no.2
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    • pp.265-291
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    • 2021
  • This paper explores the academic topography of the discourses on the anthropocene to delve into how the humanities can insightfully respond to the ecological crisis of the Earth through the lens of environmental humanities proposed in a 2020 book, The Anthropocene and the Humanities: From Climate Changes to a New Age of Sustainability by a scientific philosopher, Carolyn Merchant. By publishing her latest book, The Anthropocene and the Humanities, Merchant, a pioneering scholar of ecofeminism, has recently started into inquiring into the discourses on the anthropocene, meaning a geological age led by anthropos/humans. In one of her most distinguished works of 1980, The Death of Nature: Women, Ecology, and the Scientific Revolution, Merchant has revealed that the modern Western perception of nature, often identified with women, have been figuratively killing nature as well as women. Arguing in The Anthropocene and the Humanities that the anthropocene has been enacting a "second death of nature," which has been practically and technially killing nature, Merchant calls for the insight of the environmental humanities that help us to build a "sustainable livelihood" based on the "partnership" between human and nonhuman nature. This paper contemplates on what humanities can do in the era of anthropocenic planetarian crisis with the environmental humanistic alternatives in ecofeminist perspective to overcome the anthropocenic crisis aggravated by the covid-19 occurred at the point when the climate change was viscerally felt by the humans in the twenty first century.

Smartphone Fundus Photography in an Infant with Abusive Head Trauma (학대뇌손상 영아에서 스마트폰으로 촬영한 안저소견)

  • Kim, Yong Hyun;Choi, Shin Young;Lee, Ji Sook;Yoon, Soo Han;Chung, Seung Ah
    • Journal of The Korean Ophthalmological Society
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    • v.58 no.11
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    • pp.1313-1316
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    • 2017
  • Purpose: To report fundus photography using a smartphone in an infant with abusive head trauma. Case summary: An 8-month-old male infant presented to the emergency room with decreased consciousness and epileptic seizures that the parents attributed to a fall from a chair. He had no external wounds or fractures to the skull or elsewhere. However, computerized tomography of the brain revealed an acute subdural hematoma in the right cranial convexity and diffuse cerebral edema, leading to a midline shift to the left and effacement of the right lateral ventricle and basal cistern. The attending neurosurgeon promptly administered a decompressive craniectomy. Immediately after the emergency surgery, a fundus examination revealed numerous multi-layered retinal hemorrhages in the posterior pole extending to the periphery in each eye. He also had white retinal ridges with cherry hemorrhages in both eyes. We acquired retinal photographs using the native camera of a smartphone in video mode. The photographer held the smartphone with one hand, facing the patient's eye at 15-20 cm, and held a 20 diopter condensing lens at 5 cm from the eye in the other hand. Our documentation using a smartphone led to a diagnosis of abusive head trauma and to obtain the criminal's confession, because the findings were specific for repetitive acceleration-deceleration forces to an infant's eye with a strong vitreoretinal attachment. Conclusions: This ophthalmic finding had a key role in the diagnosis of abusive head trauma. This case presented the diagnostic use of a smartphone for fundus photography in this important medicolegal case.