• Journal of KIISE:Computer Systems and Theory
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• v.30 no.2
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• pp.78-92
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• 2003

In related to mobile communication environment, many researchers have studied problems concerning current locations of mobile users and exposure of their movements in the privacy aspect so far [1,2,3,4,5,6,7,8,9]. Among them, Kesdogan and Pfitzmann [3,6] proposed effective solutions using temporary pseudonym identification, called TP(Temporary Pseudonym ) to solve them. After that, Kesdogan et al. proposed an improved method protecting mobile users from some types of attacks of network providers in [8]. However, among their methods, in particular the method, attaching the other new device (so-called Reachability Manager) to system against active attack of network providers, is alterative rather than practical and is not clear. Moreover, it requires the other cost and overhead. Therefore we propose a practical method against active attack of network providers without attaching new device in original environments. The basie idea of proposed method is to protect a fraud act of network provider as a inside user by exchanging a secret information, which only users and network providers know, via network provider between mobile user and the trusted third party (so-called Trust Device). Moreover, we introduce a new payment protocol which applied our method.

• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.563-570
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• 2005

The purposes of this study are to examine a field test on heavy metal removal efficiency for AMD(Acid Mine Drainage) using fish bone and apatite, and to compare those results of the laboratory & the field tests. The duration of the field test was about one month and flow rates of AMD varied from 2.53 l/min to 12.8 l/min. From the result of the field test, removal efficiencies of apatite and those of fish bone are high for As, Fe, and Pb while those of fish born is higher than those of apatite far Al, Cd, Cu and Zn which are similar to the result of the previous laboratory test. In particular, average arsenic removal efficiency of apatite is higher$(84\%)$ than that of fish bone$(75\%)$ like the result of the previous laboratory test. In case of precipitates of phosphate compounds which are generated from chemical reaction between apatite/fish bone and AMD, those generated from apatite/AMD reactionform powder-shape while those created from fish bone/AMD reaction seem to be sludge. Therefore, apatite will be used as a precipitant for mine drainages having wide range of pH based on previous studies while fish bone will be applied as a precipitantfor AMD having lower PH and high concentration of heavy metals.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.3
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• pp.253-260
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• 2020

Alzheimer's disease (AD) is a chronic and progressive neurodegenerative disease that can be described by the occurrence of dementia due to a decline in cognitive function. The disease is characterized by the formation of extracellular and intracellular amyloid plaques. Amyloid beta (Aβ) is a hallmark of AD, and microglia can be activated in the presence of Aβ. Activated microglia secrete pro-inflammatory cytokines. Furthermore, S100A9 is an important innate immunity pro-inflammatory contributor in inflammation and a potential contributor to AD. This study examined the effects of metformin and α-LA on the inflammatory response and NLRP3 inflammasome activation in Aβ- and S100A9-induced BV-2 microglial cells. Metformin and α-LA attenuated inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). In addition, metformin and α-LA inhibited the phosphorylation of JNK, ERK, and p38. They activated the nuclear factor kappa B (NF-κB) pathway and the NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome. Moreover, metformin and α-LA reduced the marker levels of the M1 phenotype, ICAM1, whereas the M2 phenotype, ARG1, was increased. These findings suggest that metformin and α-LA are therapeutic agents against the Aβ- and S100A9-induced neuroinflammatory responses.

• Journal of the Korea Convergence Society
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• v.2 no.2
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• pp.47-56
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• 2011

Korea Ministry of Knowledge Economy has estimated that wind power (WP) will be occupied 37% in 2020 and 42% in 2030 of the new energy sources, and also green energies such as photovoltaic (PV) and WP are expected to be interconnected with the distribution system because of Renewable Portfolio Standard (RPS) starting from 2012. However, when a large scale wind power plant (over 3[MW]) is connected to the traditional distribution system, protective devices (mainly OCR and OCGR of re-closer) will be occurred mal-function problems due to changed fault currents it be caused by Wye-grounded/Delta winding of interconnection transformer and %impedance of WP's turbine. Therefore, when Double-Fed Induction Generator (DFIG) of typical WP's Generator is connected into distribution system, this paper deals with analysis three-phase short, line to line short and a single line ground faults current by using the symmetrical components of fault analysis and PSCAD/EMTDC modeling.

• Cartoon and Animation Studies
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• s.49
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• pp.697-712
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• 2017

In recent years, film and animation for cinematic release have embraced stereoscopic vision and the three-dimensional depth it creates for the viewer. The maturation of consumer-level virtual reality (VR) technology simultaneously spurred a wave of media productions set within 3D space, ranging from computer games to pornographic videos, to Academy Award-nominated animated VR short film Pearl. All of these works rely on stereoscopic fusion through stereopsis, that is, the perception of depth produced by the brain from left and right images with the amount of binocular parallax that corresponds to our eyes. They aim to emulate normal human vision. Within more experimental practices however, a fully rendered 3D space might not always be desirable. In my own abstract animation work, I tend to favour 2D flatness and the relative obfuscation of spatial relations it affords, as this underlines the visual abstraction I am pursuing. Not being able to immediately understand what is in front and what is behind can strengthen the desired effects. In 2015, Jeffrey Shaw challenged me to create a stereoscopic work for Animamix Biennale 2015-16, which he co-curated. This prompted me to question how stereoscopy, rather than hyper-defining space within three dimensions, might itself be used to achieve a confusion of spatial perception. And in turn, how abstract and experimental moving image practices can benefit from stereoscopy to open up new visual and narrative opportunities, if used in ways that break with, or go beyond stereoscopic fusion. Noteworthy works which exemplify a range of non-traditional, expanded approaches to binocular vision will be discussed below, followed by a brief introduction of the stereoscopic animation loop III=III which I created for Animamix Biennale. The techniques employed in these works might serve as a toolkit for artists interested in exploring a more experimental, expanded engagement with stereoscopy.

• Journal of Internet Computing and Services
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• v.12 no.5
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• pp.171-179
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• 2011

In this paper it is hypothesized that word stimuli that are presented by Google’s search word, would improve the quality of the design solution, so this research examines the effect of related search word stimuli in concept generation and analyzes the results through the processes of creative cognition. In the process of concept generation, words are given as stimuli which are generated through Google's related search and these search words are given by 5 levels. Google search is based on the collaboration philosophy. People's participation and contribution recreate knowledge and information, so these renewed and related search words update in real time by people are used as stimuli. Two problems are provided with related search words. After the design concept generation the results are analyzed by 3 bases: the usage of related search words and those of frequency, creativity, and Finke's 12 Geneplore model. These are the results of the research. Many levels of related search words are used in design concept generation but especially higher levels which are more related to search words are more used than lower levels. The usage of multi words and conjunction with higher levels and lower levels words are observed in creative results. On the creative cognitive processes, it is more creative when using association and mental transformation with the related search words than using the related search words simply. Creative outputs also use conceptual interpretation, functional inference, and contextual shifting of creative cognitive processes of Finke's 12 Geneplore model.

• Journal of Educational Research in Mathematics
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• v.22 no.2
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• pp.203-227
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• 2012

This was to investigate how the slow learners who specially belonged to low-SES, or North Korean defectors showed their errors in mathematical learning. To conduct the study, two groups for each minority group participated in the study volunteerly during the Winter vacation, in 2011. Based on the preliminary interviews, a total of 15 units were given, focusing on building mathematical basic concepts. As results, they had some errors in common. They both were in lack of understanding of the terminologies and not able to apply the meanings of definitions and theorems to a problem. Because of uncertainty of basic knowledge of mathematics, they easily lost their focus and were apt to make a mistake. Also, they showed clear differences. North Korean defectors were not accustomed to using or understanding the meanings of Chines or English in Korean words in expressing, writing mathematical terminologies and reading data on the context. Technical errors, and misinterpreted errors were found. However, students from the low SES showed that they were familiar with mathematical words and terminologies, but their errors mostly belonged to carelessness because of the lack of mastering mathematical concepts.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2000.04a
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• pp.14-15
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• 2000

현재의 농업에서 농약의 사용은 불가결한 것이다. DDT의 등장으로 농약만능시대의 막이 열린 이래 세계에서 10만종 이사의 농약이 탄생했다. 현재 전세계의 생산량은 매년 1천만 톤을 넘어섰고 일본의 경우 등록되어 있는 농약수는 원체(화합물종류)로서 367종, 상품명으로서는 약 5800 종류가 판매되고 있다. 년간 일본의 농약생산량은 약 60만 톤으로 농약의 수출량과 수입량이 거의 같기 때문에 생산량이 사용량에 상당하는 것으로 본다. 농약의 식품오염의 측면에서 보면, 단위 면적당 세계 제 1위의 농약 사용국인 일본은 시장에 유통되고 있는 농작물에도 상당한 양의 농약이 잔류하는 것으로 본다. 물론 식품위생법에 26종의 농약에 대해 53작물을 대상으로 하는 잔류농약기준이 있지만, 농약성분이 400종 이상이며 산포 대상이 되는 작물은 53작물보다 훨씬 많다. 또한 한 두 종류의 작물밖에 대상이 되지 않는 농약도 많아서 잔류농약기준은 식품의 안전성 확보면에서는 부족한 것이 많아. 따라서 농산물 생산자 스스로가 농약사용기준을 정확하게 지켜주기를 바랄 뿐이다. 한편으로는, 이러한 현실에 비추어서 농약사용이 일상화된 농업자에게 있어 농약으로 인한 건강상의 문제 또한 적지 않다. 농업자의 건강관리 대책의 일환으로 실시하는 건강진단 및 조사에 따르면, 만성적인 질환뿐만 아니라 농약산포작업후에 나타나는 증세(기침, 피부이상, 불쾌감, 두통, 인후염, 구토)를 경험한 작업자는 예방의학적인 견지에서 농업자의 농약폭로실태파악 및 교육을 해오고 있으나 그다지 설득력을 얻지 못하여 보다 확실한 인체내 흡수량을 측정하는 방법을 생각하게 되었다. 즉 뇨중 농약 대사물을 폭로지표로 하는 생물학적 모니터링(biological monitoring)을 시도, 농업현장에 있어서의 그 실증과 유용성에 대한 검토를 하고자 하였다. 농작업 가운데서 가장 위험하다고 보는 농약산포작업 (수동식 분무기를 이용한 하우스작물 및 동력분무기를 사용한 노지작물)을 대상으로 생물학적모니터링을 실시한 결과 업자의 뇨로부터 농약의 체내흡수를 반영하는 농략의 뇨 분비성 대사물을 측정할 수 있었다. 즉 뇨나 혈액등의 생체시료를 이용한 생물학적모니터링의 농약에의 응용은 서구와는 달리 대부분이 규제가 없는 소규모 자가영농으로 정해진 농약사용지침보다 많은 농약을 사용한다거나, 또는 개인의 습관이나 작업환경에 따라 폭로조건이 달라서 실질적인 폭로-흡수의 정도가 불분명한 경우등에도 충분히 대응할 수 있어 농약사용자 개개인의 농약 폭로-흡수의 정도를 분명하게 밝힐 수 있다. 게다가 평가의 결과를 농약사용의 일선에 있는 농업자에게 피드백 하여 주므로서 농약에 대한 인식을 새롭게 하고 농약취급시의 건강장해예방행동을 촉구하는 등의 효과도 높은 것으로 예방의학적인 유용성이 크다고 볼 수 있다.

• Journal of Life Science
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• v.21 no.4
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• pp.486-493
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• 2011

Nitric oxide (NO) donors are a potent inducer of heme oxygenase-1 (HO-1). However, it is unclear whether or not HO-1 expression induced by NO donors is a direct consequence of NO released by NO donors. Here, we investigated the effects of NO donors on the expression of HO-1 in primary rat articular chondrocytes. NO donors (SIN-1, SNAP, and SNP) significantly induced the accumulation of HO-1 protein accompanied by an increase in HO-1 mRNA. NO donor-induced HO-1 expression exerted cytoprotection against NO and/or superoxide-induced cell death. Guanylate cyclase signaling was not associated with Nrf2 and HO-1 expression in NO donor-treated chondrocytes. Interestingly, NO scavenger carboxy-PTIO and SOD mimetic TEMPOL markedly inhibited NO donor-induced HO-1 expression in chondrocytes. In addition, NO donor-induced HO-1 expression was completely abrogated by the peroxynitrite scavenger MnTBAP. Since peroxynitrite can be physiologcally formed in the cell through reaction of NO with superoxide, we analyzed whether or not peroxynitrite could directly induce HO-1 expression in chondrocytes. Peroxynitrite treatment in chondrocytes evoked doseand time-dependent Nrf2 and HO-1 expression. These results indicate that HO-1 expression induced by NO donors in rat articular chondrocytes is due to NO-mediated peroxynitrite rather than NO.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 1999.06a
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• pp.39-57
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• 1999

Chitin은 새우나 게 등을 비롯한 해산 갑각류의 가공 폐기물로 버려지는 부패, 악취발생 등의 환경공해를 일으키며 처리비용 등 여러 가지 문제를 야기하던 물질이지만 최근에는 부가가치가 높은 chitosan 및 chitooligosaccarides로 가공되기 때문에 폐기물의 자원화와 미이용 자원의 개발 등 여러 가지 측면에서 기대가 모아지고 있는 다당류이다. 더욱이 chitin의 탈아세틸화로 얻어지는 chitosan은 polycation의 성질을 가지고 있어서 현재 응집제로서 각종 공업 분야에 널리 이용되고 있으며 최근에는 그 외에도 다양한 생리적 기능성을 가지고 있다는 사실이 밝혀지면서 의료, 생호학, 화장품, 식품, 화학 공업 및 농업용 등 다양한 분야에 응용 가능한 신소재로서 기대가 높아지고 있다. 그런, chitosan은 생리적 기능은 우수하지만 물에 용해되지 않고 점도가 높으며 떫은맛이 나기 때문에 식품을 비롯한 기타 응용분야에 이용이 제한되고 있다. 따라서 많은 연구자들은 이와 같은 물리적인 장애를 개선함으로써 chitosan 자체가 갖는 우수한 생리적 기능을 이용할 뿐만 아니라 항종양성을 비롯한 새로운 생리적 기능을 갖는 chitosan 유도체의 개발을 시도하고 있다. Chitosan 유도체 중에서도 chitooligosaccharides는 chitosan의 가수분해로 얻어지는 저분자 화합물이므로 물에 잘 용해도며 점도가 낮고 용액이 단맛을 낼뿐만 아니라 chitosan이 갖지 않는 새로운 생리적 기능성을 갖는 것으로 알려지면서 관심이 집중되기 시작하였다. 본고에서는 chitosan과 chitooligosaccarides의 생리 활성 기능에 대한 지금까지의 연구결과를 소개하고자 한다.에 대한 면밀한 사안이 밝혀지는 경우가 많지 않다. 또한 그 발생 경위나 원인요소에 대해서는 일반에게 공개되지 않고 있어, 우리가 실천하여 식중독을 예방할 수 있는 정보가 함께 제시되지 못하는 형편이다. 따라서 본 고에서는 최근 수년간 외국에서 학교급식을 비롯한 집단급식 등에서 발생한 식중독 사례를 중심으로 고찰, 분석하였다. 이로부터 식중독 발생에 기여한 주요 원인을 찾아내고 여기서 얻어지는 교훈을 토대로 식중독 발생을 예방 및 최소화할 수 있는 실천적 대처 방안을 모색해 보고자 한다.중의 E. coli O157:H7이 연관되어있다는 보고도 있다. 목장 방문시 원유를 마신 어린이에서 HUS가 유발하였고, 균분리 결과, 농장의 소와 어린이에서 유사한 E. coli O157:H7이 분리된 바 있다. 본 연자들은 베로톡신 유형, plasmid profiles, RFLP 분석, phage type을 기초로하여 소에서 분리된 E. coli O157:H7이 사람유래주와 매우 유사함을 확인하였다.mm 및 2-6mm 난포에서의 101개(67.8%) 및 47개(50.0%) 보다 매우 낮게 나타났다. 전체 회수 난포란수도 4등급이 59.1%(149/252)로써 1, 2, 3등급의 0.4% (1/252), 7.6%(19/252) 및 32.9%(83/252)보다 높게 나타났다. 1회 평균 회수 난포란은 $\leq$2mm 난포에서 4.8$\pm$3.7개로써 2-6mm(3.0$\pm$3.4개) 및 $\geq$6mm (0.3$\pm$0.6개)보다 높았으며, 1회당 평균 8.1$\pm$5.1개의 난포란을 회수하였다. in