• 대한기계학회논문집B
• /
• 제26권4호
• /
• pp.547-554
• /
• 2002

We are facing the serious environmental pollution difficulties such as acid rain, green house effects, etc. The gaseous matter NOx, SOx, VOCs which are regarded as main factors for these current pollutions are mainly emitted from power plants and vehicles. Therefore several leading countries are regulating the emissions strictly, especially the exhaust emissions from a Diesel engine without an aftertreatment device. The objective of this study is to find out soot and NO removal characteristics focused on the emissions of a Diesel engine by using nonthermal plasma for each engine speeds and loads. Electrostatic precipitator(wire-to-plate type reactor) is used for soot removal. Radicals generated from outer air and put into a mixing chamber in the end of exhaust line are used for NO removal. Concentration of exhaust emissions is analyzed from the gas analyzer(KaneMay) and FTIR to estimate by-products.

• 대한기계학회논문집B
• /
• 제24권4호
• /
• pp.526-532
• /
• 2000

Recent studies have been directed toward obtaining a better understanding of the application of electrostatic precipitators to collect fly ash particles produced in a coal-fired power plant. Electrical resistivity can be described as the resistance of the collected dust layer to the flow of electrical current and is an important property for the collection efficiency in the electrostatic precipitator. In this paper, fly ash resistivity as a function of temperature up to $450^{\circ}C$ has been experimentally investigated using the resistivity meter consisted of the movable electrode, dust cup, and furnace. Resistivity was found to increase with increased temperature up to $200^{\circ}C$ due to the reduction of water concentration and then gradually decrease with increased temperature due to the activation of electrons. As the resistivity of fly ash in the flue gas temperature of $150^{\circ}C$ was measured >$10^{10}$ ohm cm, the efficiency of fly ash removal in the electrostatic precipitator might be expected to be low due to back-corona phenomenon. Flue gas conditioning in the electrostatic precipitator to reduce the resistivity of fly ash as required.

• 한국전기전자재료학회논문지
• /
• 제28권2호
• /
• pp.85-91
• /
• 2015

A gasoline engine automobile uses high voltage generation of the ignition coil, igniting and burning mixed fuel in the combustion chamber, which drives the engine. When the electronic control unit intermits a current supplied to the power transistor, counter electromotive force with a low voltage is generated by self induction action in the ignition primary coil and a high voltage is induced by mutual induction action with the primary ignition coil in the second ignition coil. The high voltage is supplied to the ignition plug in the combustion chamber, causing a spark, igniting the compressed mixed fuel. If a very small defect occurs inside the insulating material when a voltage is applied in said ignition coil, the performance of the insulation material will get worse and breakdown by a partial discharge of corona discharge. Thus, in this experiment, we are to contribute to improve the performance and ensure the reliability of the ignition coil by investigating partial discharge characteristics according to the change of voltage and temperature when a voltage is applied to the specimen of the epoxy molding ignition coil.

• 한국대기환경학회지
• /
• 제12권4호
• /
• pp.487-494
• /
• 1996

Simultaneous effects of $C_2H_4$ injection and heterogeneous chemical reactions on non-thermal plasma process to remove $SO_2$ and NOx from flue gas were investigated in the present experimental study. The present results showed that 40% of the electrical power can be reduced in $C_2H_4$ injection and heterogeneous chemical reaction are simultaneously included in the non-thermal plasma precess. As an effort to apply the non-thermal plasma technique to practical flue gas treatment system, a wire-plate type reactor which has technically similar geometry of industrial electrostatic precipitators is used instead of other types of reactors, such as wire-cylinder, packed-bed and surface discharge which are inappropriate to industrial application. In the present study, the photo pictures of positive streamer corona taken by ICCD camera, voltage and current oscillograms, and design criteria of a wire-plate type reactor are also shown, which are needed for industrial application of the non-thermal plasma process.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
• /
• pp.211-212
• /
• 2007

There have three kinds of partial discharge diagnosis testing: online, offline and dismantled testing on high voltage rotating machine. Our lab testing is dismantled testing, taking off pieces into individual parts of stator coil of high voltage rotating machine in laboratory. We investigate internal discharge, slot discharge, corona discharge and normal state on pre-made stator winding by using spiral patch antenna sensor. In this lab test we compare the experimental results of our spiral patch antenna sensor and reference commercial HFCT sensor.

• 공업화학
• /
• 제32권2호
• /
• pp.219-223
• /
• 2021

Considering the current COVID 19 pandemic, herein, we developed a material that can be used to fabricate a device for checking the body temperature of a person who has been exposed to influenza or corona virus. This material was formed by mixing pluronic F127 (F127) with a polydiacetylene (PDA) vesicle, which was formed with 10,12-pentacosadiynoic acid. The color of the system started to change from blue to light purple at 37 ℃, finally turning reddish at 40 ℃. Thus, the developed material can be used to detect changes in body temperature, and thus, detect signs of fever. The mixing ratio of the PDA vesicle and F127 was an important factor for controlling the temperature at which the color change started. The results showed that the color change accompanied by the separation of the PDA vesicle with F127. We believe that this phenomenon plays an important role in reducing the conjugation length in the double and triple bond of PDA.

• Journal of Information Technology Applications and Management
• /
• 제29권1호
• /
• pp.59-70
• /
• 2022

Recently, in platforms such as YouTube and Instagram, virtual characters resembling human life become the main characters, produce various contents, breathe with the public, and create the era of virtual humans. For example, existing game characters appear as virtual characters with unique AUs, or AI characters created by reflecting the public's preferences are actively communicating with the public through advertisements and SNS activities. As the consumption of video content through smart devices increases significantly in the post-corona era, virtual influencers are being used as all-round entertainers because there is little risk of personality controversy or production cost. there is a trend In this study, we investigated the characteristics of the case of being active as an influencer among the activities of a virtual character, and how the interactive aspect of the influencer appears by identifying the current situation through major cases. Combining this, based on the analysis of the influence of virtual influencers, the parts that producers should recognize are derived, and the differentiated characteristics of interactive virtual influencers are summarized. In addition, the difficulties of virtual influencers were investigated and problems were identified, and for the development of the content industry, a more favorable method for interaction was presented and suggestions were made to secure inner sincerity.

• 한국정보통신학회:학술대회논문집
• /
• 한국정보통신학회 2022년도 춘계학술대회
• /
• pp.609-611
• /
• 2022

LMS는 교육 학습 활동의 관리를 자동으로 해주는 소프트웨어로 코로나 확산으로 온라인 교육이 증가하고 있는 요즘 대부분의 교육 기관에서 사용되고 있다. LMS는 온라인 수업 뿐만 아니라 오프라인 수업과 연결지어 활용할 수 있을 만큼 활용도가 높고 광범위한 방식을 포괄하고 있다. 따라서 사회적 거리두기가 지속되었던 기간 동안 교육 기관 뿐만 아니라 재택근무 등 온라인 업무를 보기 위한 직장인에게도 유용한 소프트웨어임을 확인할 수 있었다. 이러한 LMS 기능은 향후 교육 시장과 온라인 클래스의 발전에 큰 도움이 될 것이다.

• 한국초전도ㆍ저온공학회논문지
• /
• 제10권1호
• /
• pp.15-18
• /
• 2008

To achieve high transport current without degradation under magnetic field, it is essential to artificially generate the pinning sites at which moving magnetic flux can be pinned. In this work, $ZrO_2$ nanodots were formed on the substrate surface using electro-spray deposition method. On top of the nanodots, the extended and effective pinning centers can be created. The positively charged Zr precursor solution was sprayed out from the needle using the corona discharge phenomena. Then, the sprayed precursor was deposited onto the negatively charged substrate surface followed by the heat treatment under the controlled atmosphere. Using the electrostatic force among the charged particles of precursor, evenly distributed and nano-sized dots were formed on the substrate surface. The size and density of the nanodots were studied by Atomic Force Microscopy. Also discussed are the effect of the deposition time and solution concentration on the size and density of the nanodot and processing variables in electro-spray method for the effective flux pinning centers in the superconducting films.

• 문화기술의 융합
• /
• 제8권3호
• /
• pp.501-506
• /
• 2022

COVID-19의 영향으로 로드샵과 수많은 오프라인 매장은 예전과 달리 많은 어려움을 격고 있다. 이에 대응하기 위하여 뷰티업계에서는 고객들의 수요를 충족하고자 다양한 비대면 서비스들을 선보이고 있다. 본 논문에서는 비대면 서비스 중 모바일 환경에서 이미지 기반 퍼스널 컬러 측정 기술의 품질과 제품 추천 서비스에 대한 고찰을 진행하였다. 현재 글로벌 서비스 시장에서 많이 활용되고 있는 엔진에 대한 다양한 실험과 실제 측색 장비를 활용한 컬러 측정 데이터에 대한 비교 분석, 서비스 구현 및 지표 데이터 등으로 구성되었다. 정밀한 실험결과를 위해 일관된 실험 환경에서 실험을 진행하였다. 본 논문이 이미지 기반 피부 컬러 측정에 따른 개인화 제품 추천 서비스의 확장에 활용될 수 있기를 기대한다.