• Transactions of the KSME C: Technology and Education
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• v.3 no.3
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• pp.225-232
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• 2015

The control element drive mechanism (CEDM) is an electro-mechanical device to control reactivity of the nuclear reactor. The conventional CEDM was installed on a nozzle of the reactor vessel closure head as an ex-vessel type. However, there have been demands for an in-vessel CEDM to fundamentally eliminate the rod ejection accident. Conceptual design of the in-vessel CEDM, which was developed based on the existing technology of the ex-vessel CEDM, is introduced in this paper.

• Communications of the Korean Mathematical Society
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• v.17 no.3
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• pp.535-540
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• 2002

Let X$_1$, X$_2$‥‥,X$\_$n/ be n independent and identically distributed random variables with continuous cumulative distribution function F(x). Let us rearrange the X's in the increasing order X$\_$1:n/ $\leq$ X$\_$2:n/ $\leq$ ‥‥ $\leq$ X$\_$n:n/. We call X$\_$k:n/ the k-th order statistic. Then X$\_$n:n/ - X$\_$n-1:n/ and X$\_$n-1:n/ are independent if and only if f(x) = 1-e(equation omitted) with some c > 0. And X$\_$j/ is an upper record value of this sequence lf X$\_$j/ > max(X$_1$, X$_2$,¨¨ ,X$\_$j-1/). We define u(n) = min(j|j > u(n-1),X$\_$j/ > X$\_$u(n-1)/, n $\geq$ 2) with u(1) = 1. Then F(x) = 1 - e(equation omitted), x > 0 if and only if E[X$\_$u(n+3)/ - X$\_$u(n)/ | X$\_$u(m)/ = y] = 3c, or E[X$\_$u(n+4)/ - X$\_$u(n)/|X$\_$u(m)/ = y] = 4c, n m+1.

• Natural Product Sciences
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• v.15 no.2
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• pp.90-95
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• 2009

Phytochemical investigation of the MeOH extract of the leaves of Nelumbo nucifera resulted in the isolation of five norsesquiterpenes, four flavonoids, two triterpenes and one alkaloid. Their chemical structures were characterized by spectroscopic methods to be (E)-3-hydroxymegastigm-7-en-9-one (1), (3S,5R,6S,7E)- megastigma-7-ene-3,5,6,9-tetrol (2), dendranthemoside B (3), icariside $B_2$ (4), sedumoside $F_1$ (5), luteolin (6), quercetin 3-0-${\beta}$-D-glucuronide (7), quercetin 3-0-${\beta}$-D-glucoside (8), isorhamnetin 3-0-rutinoside (9), alphitolic acid (10), maslinic acid (11), and N-methylasimilobine (12). Norsesquiterpenoids (1-5) and triterpenes (10-11) were isolated for the first time from this plant. Compounds 6 and 10-12 exhibited considerable cytotoxicity against four human cancer cell lines in vitro using a SRB bioassay.

• Journal of the Korea Society of Computer and Information
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• v.21 no.3
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• pp.17-23
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• 2016

In this paper, we propose a model of the collaborative authoring tool and its implementation results. In the 'collaborative authoring and automatic distribution system,' users can create eBooks by using partial works (primary and edited sources) on the basis of copyright information registered by the primary author. The Collaborative Authoring Tool is a part of "the collaborative authoring and automatic distribution system" developed through research on "the development of key technologies of social work protection and content mashup tools" as an R&D project granted by the Korea Copyright Commission from 2013. In the collaborative authoring and automatic distribution system, authors of primary sources such as images, audio clips and video clips for eBooks can register them together with the copyright information; users can edit the primary sources to produce secondary sources and in turn register the secondary sources on the system; and users can create and distribute eBooks by using the sources registered in the system.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.928-933
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• 2001

EGR(Exhaust Gas Recirculation) is an effective strategy to control nitrogen oxides emissions from diesel engine. The EGR reduces $NO_x$ through lowering the oxygen concentration in the combustion chamber as well as through heat absorption. However, application of EGR system is difficult because of the penalty in fuel consumption and the increase in particulate matter. The engine used for the experimental was a 3-cylinder 0.8-liter turbo-charged light duty diesel engine with an electronic EGR valve. In this study, experiments were performed at variable vehicle speeds and loads on the chassis dynamometer. To evaluate the exhaust emissions with the EGR system testing was performed using cvs-75 mode test procedure. Results of the cvs-75 mode test achieve sufficiently to meet EURO3 standards.

• Journal of Nutrition and Health
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• v.41 no.5
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• pp.402-413
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• 2008

This study was performed to investigate Apolipoprotein E phenotypes and the relationship among lipid levels, nutrient intakes, lifestyles and risk factors between subjects with and without hyperlipidemic risk. The data were collected from 675 industrial male workers who had completed annual medical examination. Compared to the normal group, the hyperlipidemic risk group in Apo E3 and E4 had significantly higher BMI (p < 0.05) and showed significantly higher body fat (%), waist circumference and WHR in all types of Apo E (p < 0.05). In addition, the hyperlipidemic risk group had significantly higher total cholesterol, LDL-cholesterol, triglyceride and AI than the normal group in all types of Apo E (p < 0.05). Intakes of protein, calcium, phosphorus, iron, vitamin A, vitamin B1, vitamin B2, vitamin C and niacin in Apo E3 were significantly lower in the hyperlipidemic risk group than in the normal group (p < 0.05). In the logistic regression analysis, after adjustment for other factors, Apo E2 + E4, waist and WHR were the significant risk factors associated with hyperlipidemia, but protein intakes were associated with significantly lower risks of hyperlipidemia (p < 0.05). In conclusion, genetic factor (Apo E2 or Apo E4), anthropometric index and nutrient intake seem to influence hyperlidemic risk. Further studies and efforts will be needed to evaluate the independent relationships among hyperlipidemic risk factors.

• Korean journal of applied entomology
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• v.10 no.1
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• pp.13-22
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• 1971

This experiment was conducted to investigate the differences of the in vitro inhibitory effect of various organephobphorua insecticides on the chlinesterase from rice stem borer and those of the toxicity of them against the insect, with special references to the relationship between the cholinesterase inhibition and the toxicity. The results obtained were summarized as follows: Phosphate compounds shelved stronger inhibitory effect on the cholinesterase than thhiophosphate compounds, but was not stronger in toxicity than the latter. Diethoxy compounds were not always stronger than dimethoxy in cholinesterase inhibition and the toxicity of organophosphorus insecticides. The organophosphorus insecticides that inhibited strongly the cholinesterase were not always stronger in the toxicity.

• Journal of the Korean GEO-environmental Society
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• v.13 no.3
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• pp.5-11
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• 2012

The abjective of this study was to study the degradation behavior and acute toxicity assessment of Triclosan and acute toxicity under E-beam irradiation. The experiments were conducted to investigate the efficts of the degradation efficiency in the initial concentration of Triclosan and the irradiation capacity of E-beam and the degree of mineralization based on a change of scavenger gas. The biological toxicity test by using on green algae, Pseudokirchneriella Subcapitata was conducted to lead the reducing toxicity. Degradation efficiency of Triclosan was improved when E-beam irradiation intensity was higher. Additionally, the % of TOC removal in each Radical scavenger gas was increased as the follows orders: $N_2O$ > $O_2$ > $N_2$, The toxicity test showed that the toxicity effect after 4 days(96hrs) was decreased by increase of E-beam irradiation intensity.

• Nuclear Engineering and Technology
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• v.15 no.1
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• pp.33-40
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• 1983

It is shown that the Shanks sequence $E_{k}$-transformation and the conventional extrapolation method are theoretically related. The $E_1$$^2$-transformation method is then applied for the multigroup diffusion problems. The diffusion code, CITATION, is modified for this study and the computing time is compared for each iteration tactics. The Equipose method, in which only sing1e inner iteration for each energy group is carried for an outer iteration, has been known as the fastest iteration method. However, in the case of 3-group problems, the proposed method, in which the number of inner iteration for the fast and thermal group is 2 and 1 respectively, gives better convergency than the Equipose method by about 12%. The double extrapolation method results in faster computing time than the single extrapolation method without computing storage problem. It is, however, to note that this method is verified only for a two-group treatment.t.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.33.1-33.1
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• 2016

Dwarf elliptical galaxies (dEs), the most abundant galaxy type in clusters, were recently shown to exhibit a wide variety in their properties. Particularly, the presence of blue cores in some dEs, what we call dE(bc), supports the scenario of late-type galaxy infall and subsequent transformation into red, quiescent dEs. While several transformation mechanisms for these dE(bc)s within cluster environment have been proposed, all these processes are able to explain only some of the observational properties of dEs. In this context, internal kinematic properties of dE(bc)s provide the most crucial evidence to discriminate different processes for the formation of these galaxies. We present Gemini Multi Object Spectrograph (GMOS) long-slit spectroscopy of two dE(bc)s in the Virgo cluster. We obtained radial profiles of velocity and velocity dispersion out to ~1.3 effective radius. We found that two dE(bc)s exhibit kinematically decoupled components as well as distinct peculiar features in velocity profiles, supporting the scenario of mergers. We also found that these galaxies are structurally compatible with low surface brightness component of blue compact dwarf galaxies. We suggest that a part of dE(bc)s in the Virgo Cluster were formed through galaxy merger in low density environment such as galaxy group or outskirt of the cluster, and then were quenched by subsequent effects within cluster environment.