• Title/Summary/Keyword: DEA method

Search Result 485, Processing Time 0.026 seconds

Parasitic Capacitive Housing Effects in a Multi-Lamps Backlight

  • Kim, Sang-Beom;Cho, Mee-Ryoung;Hong, Seong-Moon;Lee, Yong-Kon;Lee, Sang-Heok;Lee, Ji-Hoon;Lee, Joo-Young;Hong, Jin-Woo;Yang, Dong-Wook;Lee, Dea-Heung;Kim, Bong-Soo;Kang, June-Gill;Cho, Guang-Sup
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2003.07a
    • /
    • pp.639-641
    • /
    • 2003
  • The parasitic capacitance between the high voltage electrodes and the backlight housing causes lowering lamp current, electric power leakage, and leading to lower brightness and efficiency in a multi-lamps backlight. In this study a new center balance swing operation method is introduced to be minimizing those housing effects.

  • PDF

Production of $H_2$ Gas in Pyrolysis of Paper Biomass using Ni-based Catalysts (종이 바이오매스의 열분해에서 니켈 촉매에 의한 수소제조특성)

  • Choi, Yong-Keun;Chattopadhyay, Jeeta;Kim, Chul-Ho;Kim, Lae-Hyun;Son, Jae-Ek;Park, Dea-Won
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.19 no.6
    • /
    • pp.514-519
    • /
    • 2008
  • In the present study, biomass pyrolysis was done using five different kinds of catalysts with change in the support species and their compositions. Ni was loaded on alumina, ceria and alumina-ceria supports using co-precipitation method. In all the catalysts, 30wt% of nickel was loaded on the support materials. The paper used in daily writing purposes was taken into account as biomass sample. In the experiment, 19 of biomass was mixed with o.1g of each catalyst separately. Thermogravimetric analysis (TGA) was performed with all the catalysts diminished the initial degradation temperature of paper biomass sample considerably. During the pyrolysis process, the temperature was raised from room temperature to $800^{\circ}C$ with the heating rate of $10^{\circ}C$/min in the furnace. The cumulative $H_2$ volume had reached the best value of l4.02ml with the Ni/$Al_2O_3-CeO_2$ 30wt%/(50wt%-50wt%) catalysts. In presence of all the catalysts, the highest amount of $H_2$ was produced at $800^{\circ}C$, 10min. of residence time.

A Study on the attitude control of the quadrotor using neural networks (신경회로망을 이용한 쿼드로터의 자세 제어에 관한 연구)

  • Kim, Sung-Dea
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.9 no.9
    • /
    • pp.1019-1025
    • /
    • 2014
  • Recently, the studies of the Unmanned Aerial Vehicle(UAV) has been studied a variety from military aircraft to civilian aircraft and for general hobby activity aircraft. In particular, for small unmanned aircraft research for the ease of turning and hovering and Vertical-Off Take Landing(VTOL), have been studied mainly quadrotor unmanned aircraft is a type suitable for this study of small unmanned aircraft. The studies of these unmanned aircraft is the kinetic analysis requires complex processes, because these support by the aerodynamic forces on the unmanned aircraft study, and the controller design based on these dynamical analysis and experimental model analysis. In this paper, after the implementation of the basic attitude control based on a general PID controller, we propose concept design of the attitude control method on quadrotor attitude control by using the reinforcement learning algorithm of neural networks for non-linear elements not considered in the controller design.

Fabrication of a Multiplexing Sensor Probe for Measuring the Blade Deflection of a Wind Power Generator (풍력발전기 블레이드 처짐 측정을 위한 다중화 센서 탐촉자 설계 제작)

  • Kim, Ji-Dea;Lee, Dong-Ju
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.23 no.2
    • /
    • pp.178-185
    • /
    • 2014
  • This paper describes a fabrication multiplexing sensor probe that employs a fiber Bragg grating(FBG) based on multiple measurements to determine the blade deflection of a wind power generator the reliability analysis of this probe is also presented. To diminish the temperature sensitivity of the FBG sensor, we form multiple CFRPs onto the upper and lower layers of the FBG and package it with an epoxy resin. As a result, the depth of the CFRP is 1mm, and the temperature sensitivity is $2.39pm/^{\circ}C$. We construct a sensor network utilizing the fabricated sensor with a blade beam model. As the number of pendulums is increased on the fore-end of the beam, the strain value is measured. The strain variation is calculated from the measurement of the load on the blade beam model by monitoring the strain of the FBG sensor. When the linear equation is applied, the strain error is 0.4% and when the finite difference method is used, the tip deflection error is 3.3%. The displacement error derived from the strain value of the FBG sensor is 4.39%. The calculated result between the measured value of the dead-end of the beam and the strain is less than 2.46% tip distortion error. Therefore, our proposed multiplexing sensor probe is a low-cost and high-reliability solution for a commercial wind power generator.

A Herbological study on the herbs in 3 Kinds of common Scrophulariaceae (상용(常用) 현삼과(玄蔘科) 한약재(韓藥材) 3종(種)의 본초학적(本草學的) 연구(硏究))

  • Yoon, In-Su;Song, Hyo-June;Kim, Se-Jeong;Kang, Dea-hun;Kim, Jong-moon;Choi, Go-Ya;Ju, Young-Sung
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
    • /
    • v.20 no.3
    • /
    • pp.127-137
    • /
    • 2007
  • Objects : This study was designed to determine origin-plants of 3 kinds of Scrophulariaceae herbs reported worldwide 220 families 3000 species, domestic 21 families 55 species by researching efficacy of each herb. Furthermore the objects of study were confirmation of genuine species and substitution species standing on the results. Methods : In this studies, the origin-plants and efficacy were determined by bibliographic method. Results : The results indicate that 1. There were total 15 species of original plants of Scrophulariaceae herbs, 9 species for Radix Scrophulariae, 4 species for Radix Rehmanniae Recens, 2 species for Rhizoma Picrorrhizae. 2. In the view of authenticity of Radix Scrophulariae, there were 2 genuine species, 1 species for substitution, and study of 6 species later on. 3. In the view of authenticity of Radix Rehmanniae Recens, there were 2 genuine species, 1 species for substitution, and study of 1 species later on. 4. In the view of authenticity of Rhizoma Picrorrhizae, all the original species was genuine species. 5. The each efficacy of origin-plants were reported in the main subject. Conclusions : The 15 original plants were present among the 3 medicinal herbs in the common family scrophul ariaceae. There were 2 genuine species in Radix Scrophulariae and Rhizoma Picrorrhizae. All the original species was genuine species in Rhizoma Picrorrhizae.

  • PDF

Extraction of Forensic Evidence and Hacking Attacks about IP-PBX (IP-PBX에 대한 해킹공격과 포렌식 증거 추출)

  • Park, Dea-Woo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2013.05a
    • /
    • pp.197-200
    • /
    • 2013
  • Internet phone, communication cost and easy-to-use low-cost compared to the PSTN is a mobile phone of a conventional, and use of the Internet phone is spreading. Construction as part of the broadband convergence network(BCN), Internet service provider(KT, SKT, LG) has converted to Internet phone telephone network to all government agencies. In addition, members of the public also have an Internet phone service that you are using. In this paper, we analyze the hacking attack on IP-PBX in the IETF SIP-based that are used in Internet telephony, to the study. The test bed is constructed in the same way as the Internet telephone system to perform studies carried hacking attacks on IP-PBX, analyze the results and to extract evidence forensics. When used in crime by hacking the Internet telephone, we propose a method which can be used as evidence in forensic having legal effect.

  • PDF

Synthesis and Surface Active Properties of Diglycerol N-Acyl Glutamic Acid Esters (디글리세롤 N-아실 글루탐산 에스테르류의 합성 및 계면성)

  • Jeong, Hwan-Kyeong;Jeong, No-Hee;Nam, Ki-Dea
    • Applied Chemistry for Engineering
    • /
    • v.5 no.2
    • /
    • pp.247-254
    • /
    • 1994
  • Nonionic surfactants, diglycerol N-acyl glutamates were prepared through the esterification of N-acryl glutamic acids and glycidol in the presence of quarternary ammonium salts. Their cmc evaluated by the surface tension method was $0.15{\sim}0.75mol/{\ell}$, and the surface tension of aqueous solution was decreased to 28~35dyne/cm. L-DGLG with acyl group of carbon number of 12 showed good foaming power and emulsifying power, and the emulsifying power in toluene was stronger than in soybean oil. Dispersion effect of L-DGPG and L-DGSG with acyl group of carbon number of 16 and 18 in carbon black and ferric oxide were higher than L-DGLG. All of them showed good biodegradability at $20^{\circ}C$.

  • PDF

Evaluation for Efficacies of Commercial Sanitizers and Disinfectants against Bacillus cereus Strains

  • Kim, Il-Jin;Ha, Ji-Hyoung;Kim, Yong-Su;Kim, Hyung-Il;Choi, Hyun-Chul;Jeon, Dea-Hoon;Lee, Young-Ja;Kim, Ae-Jung;Bae, Dong-Ho;Kim, Keun-Sung;Lee, Chan;Ha, Sang-Do
    • Food Science and Biotechnology
    • /
    • v.18 no.2
    • /
    • pp.537-540
    • /
    • 2009
  • Bactericidal efficacies of various sanitizers and disinfectants against 10 Bacillus cereus strains isolated from Korean foods and 8 standard B. cereus strains were investigated. The sanitizing capabilities of ethanol, iodine, chloride, quaternary ammonium, hydrogen peroxide, and peroxide acetic acid were investigated using the EN 1276 method based on quantitative suspension testing. The resistance against sanitizers and disinfectants was higher for wild-type than standard strains, and the bactericidal activities decreased in dirty conditions. Ethanol, chlorine, and iodine at the maximum level allowed under Korean food sanitation laws showed a great effectiveness against B. cereus. Hydrogen peroxide at 1,100 ppm showed the lowest bactericidal activity against B. cereus. These results indicate that the legally allowed maximum concentrations of sanitizers and disinfectants in Korea do not reduce all B. cereus strains by at least $5\;{\log}_{10}\;CFU/mL$.

A Study of Connection of Facility DB for People with Disability to Smartphone for Location and Voice Recognition and QR Code Recognition and to Navigation (위치 음성인식 QR코드가 인식된 스마트폰과 네비게이션에 대한 장애인 편의시설 DB 연결)

  • Yang, Sung-Yong;Park, Dea-Woo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2013.10a
    • /
    • pp.177-180
    • /
    • 2013
  • The number of people with a disability registered in the Korea's Ministry of Health and Welfare is more than 2.5 million in 2010, and approximately 2.51 million as of late 2012. In consideration of potential disabilities led by aging which is in fast progress in Korea, the number of people with a disability will further increase. It is necessary to study the method of enabling people with a disability to easily access facilities and of using facilities for people with a disability, in order to comply with the Disability Discrimination Act (DDA) which is enforced in Korea. In this study, a smartphone recently used more and more is used to develop a smartphone which can recognize locations, voice and the QR code for enabling people with a disability to recognize them. The developed smartphone for people with a disability is connected to a database established as a facility for people with a disability, and to the navigation system in the wheelchair accessible call taxis, to enable the disability database to be used. This study will contribute to observing the Disability Discrimination Act of Korea, and improving the national welfare system by enhancing the disability care services.

  • PDF

The Analysis of the APT Prelude by Big Data Analytics (빅데이터 분석을 통한 APT공격 전조 현상 분석)

  • Choi, Chan-young;Park, Dea-woo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2016.05a
    • /
    • pp.317-320
    • /
    • 2016
  • The NH-NongHyup network and servers were paralyzed in 2011, in the 2013 3.20 cyber attack happened and Classified documents of Korea Hydro & Nuclear Power Co. Ltd were leaked on December in 2015. All of them were conducted by a foreign country. These attacks were planned for a long time compared to the script kids attacks and the techniques used were very complex and sophisticated. However, no successful solution has been implemented to defend an APT attack thus far. Therefore, we will use big data analytics to analyze whether or not APT attack has occurred in order to defend against the manipulative attackers. This research is based on the data collected through ISAC monitoring among 3 hierarchical Korean defense system. First, we will introduce related research about big data analytics and machine learning. Then, we design two big data analytics models to detect an APT attack and evaluate the models' accuracy and other results. Lastly, we will present an effective response method to address a detected APT attack.

  • PDF