• Journal of the Korean Electrochemical Society
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• v.20 no.3
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• pp.49-54
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• 2017

We develop a ceramic composite separator prepared by coating $ZrO_2$ nanoparticles with a poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) copolymer on a polyvinyl alcohol (PVA) mechanical support prepared by electrospinning technique to improve thermal properties. The gurley number of the ceramic composite separator shows much lower value than that of a PE separator even though it possesses the polymeric coating layer with ceramic nanoparticles. In addition, the proposed sample shows higher electrolyte uptake than PE separator, leading to enhancing the ionic conductivity of the proposed sample and, by extension, the rate discharge properties of lithium ion batteries. Thermal stability of the ceramic composite separator is dramatically improved without any degradation in electrochemical performance compared to the performance of conventional PE separators.

• Journal of Environmental Policy
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• v.14 no.3
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• pp.95-118
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• 2015

The 2015 Agreement, an initial architect of the Post-2020 Regime, is expected to be adopted at the twenty-first session of the Conference of Parties to be held in Paris in 2015. We discussed key characteristics of the Post-2020 Regime and applications of differentiation which is most contentious issue in the Post-2020 negotiation. In the Post-2020 Regime, automatic ambition increases of Parties could be accomplished through applications of the circular nature of Intented Nationally Determined Contributions (INDC) as well as the progression of mitigation efforts. In terms of differentiation, it would be better to advocate a new method to applying differentiation in the Post-2020 Regime taking into account our own national circumstances. Specifically, promotion of self-differentiation which fits nearly with the philosophy of INDC could be an alternative. In order to promote self-differentiation, rules to apply self-differentiation needs to be devised, and the purpose of such rules should be the ambition increase.

• Journal of the Korean Data and Information Science Society
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• v.28 no.4
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• pp.755-768
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• 2017

As Big Data becomes the core of the fourth industrial revolution, big data-based processing and analysis capabilities are expected to influence the company's future competitiveness. Comparative studies of RHadoop and RHIPE that integrate R and Hadoop environment, have not been discussed by many researchers although RHadoop and RHIPE have been discussed separately. In this paper, we constructed big data platforms such as RHadoop and RHIPE applicable to large scale data and implemented the machine learning algorithms such as multiple regression and logistic regression based on MapReduce framework. We conducted a study on performance and scalability with those implementations for various sample sizes of actual data and simulated data. The experiments demonstrated that our RHadoop and RHIPE can scale well and efficiently process large data sets on commodity hardware. We showed RHIPE is faster than RHadoop in almost all the data generally.

• The KIPS Transactions:PartC
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• v.14C no.5
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• pp.439-452
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• 2007

We study on the privacy preserving data mining, PPDM for short, by using randomization. The theoretical PPDM based on the secure multi-party computation techniques is not practical for its computational inefficiency. So we concentrate on a practical PPDM, especially randomization technique. We survey various privacy measures and study on the privacy preserving mining of association rules by using randomization. We propose a new randomization operator, binomial selector, for privacy preserving technique of association rule mining. A binomial selector is a special case of a select-a-size operator by Evfimievski et al.[3]. Moreover we present some simulation results of detecting an appropriate parameter for a binomial selector. The randomization by a so-called cut-and-paste method in [3] is not efficient and has high variances on recovered support values for large item-sets. Our randomization by a binomial selector make up for this defects of cut-and-paste method.

• The KIPS Transactions:PartB
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• v.18B no.3
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• pp.139-146
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• 2011

The color correction is the important process of influencing on the picture quality of the 3D stereoscopic images. Existing colorcorrecting methods handle the processing intensifying a correspondence among a left and right image using a histogram based on any one side. In case of color correction based on a histogram, it is difficult to correct tone of image, because the color temperature is not converted enough. And in this paper, the color temperature correction and color consistency correction is proposed without using histogram. The proposed color correction method by color temperature gives 3 in CIE-${\Delta}E$ for each pixel on the images captured with same illuminants and the conventional gives similar results. For color consistency, the proposed gives 9 in CIE-${\Delta}E$ on the images captured with different illuminants while the conventional gives 18. The proposed method shows better results than the conventional in color consistency processing.

• Journal of Sensor Science and Technology
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• v.7 no.4
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• pp.243-253
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• 1998

PVC membrane, which has been used for membrane of electrolyte sensors, shortened sensor lifetime due to poor adhesion to sensor surface and exhibited difficulty in standardization and mass-production. To overcome these problems, the membrane solution was prepared with neutral carrier, matrix(TEOS:DEDMS=1:3), solvent(ethanol), and a catalyzer(HCl). The fabricated electrolyte sensors showed typical electrical characteristics of MISFET (metal-insulator-semiconductor field-effect transistor). The K-, Ca- and Na-ISFETs showed sensitivity of 53, 25 and 50 mV/decade in wide concentration range, respectively. The response time was about 90 seconds and the drift was 0.05mV/hour. These results suggest that the sol-gel method and the lift-off technique can be applied to formation of membranes and expected to improve mass-productivity, standardzation of the sensors.

• The Korean Journal of Archival Studies
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• no.65
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• pp.7-46
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• 2020

Since the launch of the Moon Jae-in government in May 2017, the records and archives community hoped to overcome the delays in records and archives management over the past nine years and to pursue record and archives management innovation. This article focuses on the record and archives management innovation that the National Archives of Korea has been pursuing in the public records and archives management sector for about 3 years until the first half of 2020, and evaluates the progress and contents focusing on the main agent, innovation plan, revision of laws, and major events.

• Resources Recycling
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• v.25 no.5
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• pp.14-27
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• 2016

Theoretical reviews of integrated gasification combined cycle one of the clean coal technologies and trends in the study and technology development for high temperature desulfurization sorbents were investigated. Reactivity, durability and abrasion resistance is an important key for development of high temperature desulfurization sorbents, the kind of things include calcium, zinc, manganese, iron and copper-based sorbents. Current status of high temperature desulfurization sorbents, manufacturing techniques of zinc-based sorbent in advanced countries has commercialized. In case of Korea, various research studies are underway to commercialize the Zn and non Zn-based high temperature desulfurization sorbents to cheaper and superior capability using various supports.

• The KIPS Transactions:PartD
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• v.16D no.5
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• pp.691-700
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• 2009

An event means a flow which has a time attribute such as the a symptom of patients, an interval event has the time period between the start-time-point and the end-time-point. Although there are many studies for temporal data mining, they do not deal with discovering knowledge from interval event such as patient histories and purchase histories. In this paper, we suggest a method of temporal data mining that finds association rules of event causal relationships and predicts an occurrence of effect event based on discovered rules. Our method can predict the occurrence of an event by summarizing an interval event using the time attribute of an event and finding the causal relationship of event. As a result of simulation, this method can discover better knowledge than others by considering a lot of supports of an event and finding the significant rare relation on interval events which means an essential cause of an event, regardless of an occurrence support of an event in comparison with conventional data mining techniques.

• Informatization Policy
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• v.22 no.1
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• pp.73-95
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• 2015

This research has a purpose to verify whether the Internet diffusion through the Official Development Assistance (ODA) can bring about democratic changes in authoritarian political system of developing countries. This research has found out that IT ODA has 'positive(+)' effect on the Internet diffusion in recipient countries. It seems to support the expectation of donor countries that they can lead the political democratization by constructing infrastructure and promoting the use of the Internet. However, as the impact of IT ODA on the Internet diffusion is not considerable as well as the Internet diffusion has no strong influence on the development of democracy in developing countries, and also each of these aspects of countries looks different, it is hard to see that the democratization hypothesis based on the optimistic technological determinism is reasonable. Therefore, this paper argues that IT ODA must be based on not blind optimism that IT transfer will lead to the political democratization in developing countries, but the social structuralism which is based on distinctiveness and uniqueness of countries. and suggests that the discuss of the effect of IT ODA proceed with the constructive way.