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Data-Mining-Based Coronary Heart Disease Risk Prediction Model Using Fuzzy Logic and Decision Tree
Kim, Jaekwon,Lee, Jongsik,Lee, Youngho Korean Society of Medical Informatics 2015 Healthcare Informatics Research Vol.21 No.3
<P><B>Objectives</B></P><P>The importance of the prediction of coronary heart disease (CHD) has been recognized in Korea; however, few studies have been conducted in this area. Therefore, it is necessary to develop a method for the prediction and classification of CHD in Koreans.</P><P><B>Methods</B></P><P>A model for CHD prediction must be designed according to rule-based guidelines. In this study, a fuzzy logic and decision tree (classification and regression tree [CART])-driven CHD prediction model was developed for Koreans. Datasets derived from the Korean National Health and Nutrition Examination Survey VI (KNHANES-VI) were utilized to generate the proposed model.</P><P><B>Results</B></P><P>The rules were generated using a decision tree technique, and fuzzy logic was applied to overcome problems associated with uncertainty in CHD prediction.</P><P><B>Conclusions</B></P><P>The accuracy and receiver operating characteristic (ROC) curve values of the propose systems were 69.51% and 0.594, proving that the proposed methods were more efficient than other models.</P>
Kim, Juchan,Jeoung, Jaekwon,Jeon, Jonghyun,Kim, Jip,Mok, Young Sun,Ha, Kyoung-Su Elsevier 2019 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.377 No.-
<P><B>Abstract</B></P> <P>A dielectric barrier discharge (DBD) plasma reactor was employed for non-oxidative coupling of methane. The coupling reaction in the DBD plasma bed was conducted near atmospheric pressure and room temperature. In the bed, dielectric materials such as ordered mesoporous silica (KIT-6), sea sand silica, and α-Al<SUB>2</SUB>O<SUB>3</SUB> were employed. This non-catalytic reaction system could successfully activate CH bond to produce methyl radicals and light hydrocarbons without additional thermal energy and oxidant molecules. The gap distance between dielectric particles was determined by their sizes, which was experimentally shown. The effects of gap distance were found significant on the conversion and the selectivity. The existence of maximum conversion at a specific gap distance was experimentally observed and could be described successfully by using a newly developed concept of micro-electrodes. Based on the concept, the minimum threshold electric potential difference between the dielectric particles could be successfully estimated, where the conversion was shown to be maximized. Furthermore, it seemed quite possible to control the compositions of ethane, ethylene, and acetylene by properly adjusting the size or the gap distance of particles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The methane conversion shows its maximum in terms of particle size. </LI> <LI> The concept of microelectrodes explains the existence of maximum conversion. </LI> <LI> By adjusting particle size, selectivity can be controlled without catalyst. </LI> <LI> In terms of coke formation, non-porous silica particles are favored. </LI> <LI> Coke is more produced when large particles are used. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Regeneration of deactivated H-ZSM-5 for aromatization by dielectric barrier discharge plasma
Kim, Mahnjung,Jeoung, Jaekwon,Kim, Juchan,Ha, Kyoung-Su Elsevier 2019 Applied Catalysis A Vol.575 No.-
<P><B>Abstract</B></P> <P>A dielectric barrier discharge (DBD) plasma regeneration reaction was conducted at atmospheric pressure and temperature. This method was found to be very effective in removing carbon deposits after a non-oxidative aromatization from acetylene. When a fresh H-ZSM-5 catalyst was used for the aromatization, coke was by-produced and it could be ascribed to the primary reason for deactivation. By applying the DBD plasma to the deactivated catalyst bed at ambient temperature and pressure, the removal of carbon deposition with microdischarge and aeration was very effective; therefore, it is believed that additional thermal activation might not be necessary. More amount of coke was removed by supplying higher power to the catalyst bed. According to the results of XRD, physisorption, <SUP>27</SUP>Al MAS NMR, and NH<SUB>3</SUB>-TPD analyses, it was confirmed that the structure and the acid site distribution of H-ZSM-5 were successfully retained even after the plasma treatment. Aromatization over the plasma-regenerated catalyst led to mild deactivation at the early stage and afforded comparable BTX selectivity to fresh H-ZSM-5 catalyst. Compared with the results obtained using the thermally regenerated catalyst, the structural stability was found to be higher and the BTX selectivity was kept higher during most of the reaction time for the plasma-regenerated catalyst.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Carbon deposit from aromatization is effectively removed by a DBD plasma. </LI> <LI> The method is conducted at ambient pressure and temperature. </LI> <LI> The method does not deform the structure of dielectric material in the bed. </LI> <LI> The plasma-regenerated catalyst suppresses the excessive wasting of acetylene. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Jaekwon Shin,Vinayagam Mariappan,Deokgun Woo,Junghoon Lee,Jisung Lee,Minsoo Kim,Jintae Kim 한국인터넷방송통신학회 2018 Journal of Advanced Smart Convergence Vol.7 No.1
In addition to the instability of energy import costs caused by the depletion of petroleum resources, which is a representative energy resource, and the strengthening of various regulations such as the convention on climate change, the plant for bio energy production, which is being watched as the next generation energy, and became subject of various complaints. In order to solve this problem, the bio-plant is underground and the ground is parked, making the convenience and accessibility of citizens more and more accessible. In this situation, the development of bioenergy production technology also increases the risk factor in bioenergy production process. Accordingly this paper explains method about apply the wide angle camera based AOA algorithm to the bio plant to prevent the accidents from spreading due to the lack of facilities and safety devices and the aging of the facilities and suggests a technique that can quickly identify the location and direction when it occurs.
Phase Control Using Open-Stubs for Programmable SAW-based RFIDs
Jaekwon Kim,Dohyung Kim,범진욱,장기훈,윤영중 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.2
SAW (surface acoustic wave) tags are for passive RFID (radio frequency identication) systems. To overcome the drawbacks of current SAW RFIDs, which cannot be programmed after fabrication, we propose a technique to make the SAW ID tag programmable even after manufacturing. Control of the re ector bus-bar stub was used to change the phase of the reflected signals. The length of the bus-bar stub can be modied by line cutting using lasers and/or by connecting two lines by using conductive ink. The proposed SAW ID tag programs data and increases data capability.
Real-time imaging by use of second-harmonic generation in a beta-barium borate crystal
Jaekwon Kim,Myoungsik Cha,Chang Won Kim,Gyerok Jeon,Hwan Hong Lim,Jung Hoon Ro,Oc-Yeub Jeon 한국물리학회 2005 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.47 No.6
Non-collinear second-harmonic generation (SHG) was performed using a beta-barium-borate crystal, aiming at real-time imaging through a scattering medium. In the present experiment, we successfully obtained a high resolution real-time image of the second-harmonic beam. Detailed analyses are given for the thickness of the nonlinear crystal and our resolution of the SHG imaging system.