• Title/Summary/Keyword: High power application

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The development of a bluetooth based portable wireless EEG measurement device (블루투스 기반 휴대용 무선 EEG 측정시스템의 개발)

  • Lee, Dong-Hoon;Lee, Chung-Heon
    • Journal of IKEEE
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    • v.14 no.2
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    • pp.16-23
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    • 2010
  • Since the interest of a brain science research is increased recently, various devices using brain waves have been developed in the field of brain training game, education application and brain computer interface. In this paper, we have developed a portable EEG measurement and a bluetooth based wireless transmission device measuring brain waves from the frontal lob simply and conveniently. The low brain signals about 10~100${\mu}V$ was amplified into several volts and low pass, high pass and notch filter were designed for eliminating unwanted noise and 60Hz power noise. Also, PIC24F192 microcontroller has been used to convert analog brain signal into digital signal and transmit the signal into personal computer wirelessly. The sampling rate of 1KHz and bluetooth based wireless transmission with 38,400bps were used. The LabVIEW programing was used to receive and monitor the brain signals. The power spectrum of commercial biopac MP100 and that of a developed EEG system was compared for performance verification after the simulation signals of sine waves of $1{\mu}V$, 0~200Hz was inputed and processed by FFT transformation. As a result of comparison, the developed system showed good performance because frequency response of a developed system was similar to that of a commercial biopac MP100 inside the range of 30Hz specially.

Formulation and Application of UV-Cured Hard Coating Compounds for PVC Tile (PVC 바닥상재용 광경화형 하드 코팅액의 제조 및 응용에 관한 연구)

  • Park, Bo-Ram;Yoon, Hyun-Jung;Zhao, Hong;Ha, Jin-Wook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.9
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    • pp.2396-2401
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    • 2009
  • This study is on development of UV-cured hard coating compounds which have more improved abrasion resistance than existing UV-cured urethane-acrylic resin, to prevent a surface of a widely used PVC tile as a constructive material from being scratched. To make a high abrasion resistant hard coating solution compared to UV-cured urethane-acrylic resin which has no abrasion resistance and been used for PVC tiles, we added powder substances of different abrasion resistant level, $Al_2O_3$(Al-160SG-3), $Al(OH)_3$(SH-8W), $SiO_2$(KS-5000), etc., to the resin, changing their contents from 10% to 30% against quantities of resin, and compounded it using Ring-Mill. After coating PVC tiles with the hard coating solution using bar-coating method that can adjust a thickness, we estimated some surface properties-abrasion resistance, pencil hardness, adhesive power, thickness of coating, and so on. As a result, a hard coating solution added 30% $Al_2O_3$ powder to the resin had the finest surface properties-the first grade in abrasion resistance, H in pencil hardness, 100% in adhesive power, and a hard coating solution which showed excellent solidity and abrasion resistance has smaller particle size, higher powder content, and thicker coating thickness.

Design of Synchronous 256-bit OTP Memory (동기식 256-bit OTP 메모리 설계)

  • Li, Long-Zhen;Kim, Tae-Hoon;Shim, Oe-Yong;Park, Mu-Hun;Ha, Pan-Bong;Kim, Young-Hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.7
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    • pp.1227-1234
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    • 2008
  • In this paper is designed a 256-bit synchronous OTP(one-time programmable) memory required in application fields such as automobile appliance power ICs, display ICs, and CMOS image sensors. A 256-bit synchronous memory cell consists of NMOS capacitor as antifuse and access transistor without a high-voltage blocking transistor. A gate bias voltage circuit for the additional blocking transistor is removed since logic supply voltage VDD(=1.5V) and external program voltage VPPE(=5.5V) are used instead of conventional three supply voltages. And loading current of cell to be programmed increases according to RON(on resistance) of the antifuse and process variation in case of the voltage driving without current constraint in programming. Therefore, there is a problem that program voltage can be increased relatively due to resistive voltage drop on supply voltage VPP. And so loading current can be made to flow constantly by using the current driving method instead of the voltage driving counterpart in programming. Therefore, program voltage VPP can be lowered from 5.9V to 5.5V when measurement is done on the manufactured wafer. And the sens amplifier circuit is simplified by using the sens amplifier of clocked inverter type instead of the conventional current sent amplifier. The synchronous OTP of 256 bits is designed with Magnachip $0.13{\mu}m$ CMOS process. The layout area if $298.4{\times}314{\mu}m2$.

Techno-Economic Analysis of Reversible Solid Oxide Fuel Cell System Couple with Waste Steam (폐스팀을 이용한 가역 고체산화물 연료전지의 기술적 경제적 해석)

  • GIAP, VAN-TIEN;LEE, YOUNG DUK;KIM, YOUNG SANG;AHN, KOOK YOUNG
    • Journal of Hydrogen and New Energy
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    • v.30 no.1
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    • pp.21-28
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    • 2019
  • Reversible solid oxide fuel cell (ReSOC) system was integrated with waste steam for electrical energy storage in distributed energy storage application. Waste steam was utilized as external heat in SOEC mode for higher hydrogen production efficiency. Three system configurations were analyzed to evaluate techno-economic performance. The first system is a simple configuration to minimize the cost of balance of plant. The second system is the more complicated configuration with heat recovery steam generator (HRSG). The third system is featured with HRSG and fuel recirculation by blower. Lumped models were used for system performance analyses. The ReSOC stack was characterized by applying area specific resistance value at fixed operating pressure and temperature. In economical assessment, the levelized costs of energy storage (LCOS) were calculated for three system configurations based on capital investment. The system lifetime was assumed 20 years with ReSOC stack replaced every 5 years, inflation rate of 2%, and capacity factor of 80%. The results showed that the exergy round-trip efficiency of system 1, 2, 3 were 47.9%, 48.8%, and 52.8% respectively. The high round-trip efficiency of third system compared to others is attributed to the remarkable reduction in steam requirement and hydrogen compression power owning to fuel recirculation. The result from economic calculation showed that the LCOS values of system 1, 2, 3 were 3.46 ¢/kWh, 3.43 ¢/kWh, and 3.14 ¢/kWh, respectively. Even though the systems 2 and 3 have expensive HRSG, they showed higher round-trip efficiencies and significant reduction in boiler and hydrogen compressor cost.

Influence of Charging Condition of Al-dross on Maximum Concentration of Al in Molten Steel : Fundamental study for improvement of chemical energy in EAF process (용강 중 Al 최대 농도에 대한 Al 드로스 장입 조건의 영향: 전기로 공정 내 화학 에너지 향상을 위한 기반 연구)

  • Kim, Gyu-Wan;Kim, Sun-Joong
    • Resources Recycling
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    • v.28 no.4
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    • pp.44-50
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    • 2019
  • In the electric arc furnace process, the chemical energy such as the heat of oxidation reaction and the heat of carbon combustion etc. is consumed as 30% of the total input energy. In order to reduce $CO_2$ emission in EAF, it is necessary to decrease the use of electric power energy during scrap melting stage and increase the use of chemical energy. In general, when the carbon materials is individually charged into the molten steel, the carbon materials floated to the slag layer due to low density before it is dissolved in molten steel. When the concentration of carbon in the molten steel is high, the combustion energy of carbon by oxygen injection can lower the electric power energy and improve the chemical energy consumption. Therefore, an efficient charging methods of carbon material is required to increase the efficiency of carbon combustion heat. On the other hand, Al-dross, which is known as a by-product after Al smelting, includes over 25 mass% of metallic Al, and the oxidation heats of Al is lager than that of carbon. However, the recycling ratio fo Al-dross was very low and is almost landfilled. In order to effectively utilize the heats of oxidation of Al in Al-dross, it is necessary to study the application of Al-dross in the steel process. In this study, the dissolution efficiency of carbon and aluminum in molten steel was investigated by varying the reaction temperature and the mixing ratios of coke and Al-dross.

A Study on Improvement of Storage Safety through Quality improvement of Torpedo Propulsion Battery (어뢰 추진전지 품질개선을 통한 저장안정성 향상에 관한 연구)

  • Jang, Min-Ki
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.7
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    • pp.291-298
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    • 2019
  • We describe the improvement of insulation performance and the prevention of electrolyte leakage in a single cell in order to prevent the fuming phenomenon caused by leakage of electrolyte in a lithium secondary battery in a submerged weapon (torpedo) operated in Korea. A torpedo using lithium secondary battery as a main power source (propulsion battery) can induce the heat and fuming phenomenon, which makes it inconvenient for naval equipment operation in Korea. In the simulation test, the electrolyte of some battery cells leaked in the battery pack unit, leading to a short circuit between the main power circuit and the terminal tab of the high voltage part. We analyzed the characteristics and mechanism of the lithium secondary battery during this heat generation and fuming phenomenon. In order to prevent leakage of the electrolyte in the lithium secondary battery, the design was improved via fundamental (terminal tap enhancement) and complementary (insulation block selection and installation) measures. Comparison of the performance test before and after the improvement showed that the tensile strength of the tap terminal was improved about 2 times and the withstand voltage characteristic was improved. The application of quality improvement measures resulted in no fuming even after more than 3 years of field operation. This result is expected to improve the operation and storage stability of the torpedo propulsion cell.

NUWARD SMR safety approach and licensing objectives for international deployment

  • D. Francis;S. Beils
    • Nuclear Engineering and Technology
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    • v.56 no.3
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    • pp.1029-1036
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    • 2024
  • Drawing on the deep experience and understanding of the principles of nuclear safety, as well as many years of nuclear power plant design and operation, the EDF led NUWARD SMR Project is developing a design for a Small Modular Reactor (SMR) of 340 MWe composed of two 170 MWe independent units, that will supplement the offering of high-output nuclear reactors, especially in response to specific needs such as replacement of fossil-fuelled power plants. NUWARD SMR is a mix of proven and innovative design features that will make it more commercially competitive, while integrating safety features that comply with the highest international standards. Following the principles of redundancy and diversity and rigorous application of Defence in Depth (DID), with an international view on nuclear safety licensing, the Project also incorporates new safety approaches into its design development. The NUWARD SMR Project has been in development for a number of years, it entered conceptual design formally in mid-2019 and entered Basic Design in 2023. The objective of the concept design phase was to confirm the project technological choices and to define the first design configuration of the NUWARD SMR product, to document it, in order to launch pre-licensing with the French Safety Authority (ASN) and to define its estimated cost and its subsequent development and construction schedules. As a delivery milestone the Safety Options file (called the Dossier d'Options de Sûreté (DOS)) has been submitted to ASN in July 2023 for their opinion. An integral part of the NUWARD SMR Project, is not only to deliver a design suitable for France and to satisfy French regulation, but to develop a product suitable and indeed desirable, for the international market, with a first focus in Europe. In order to achieve its objectives and realise its market potential, the NUWARD SMR Project needs to define and realise its safety approach within an international environment and that is the key subject of this paper. The following paper: • Summarises the foundation principles and technological background which underpin the design; • Contextualises the key design features with regard to the international safety regulatory framework with particular emphasis on innovative passive safety aspects; • Illustrates the Project activities in preparation for first licensing in France, and also a wider international view via the ASN led Joint Early Review of the NUWARD SMR design, including Finnish and Czech Republic regulators, recently joined by the Swedish, Polish and Dutch regulators; • Articulates the collaborative approach to design development from involvement with the Project partners (the Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Naval Group, TechnicAtome, Framatome and Tractebel) to the establishment of the International NUWARD Advisory Board (INAB), to gain greater international insight and advice; • Concludes with the focus on next steps into detailed design development, standardisation of the design and its simplification to enhance its commercial competitiveness in a context of further harmonisation of the nuclear safety and licensing requirements and aspirations.

A Study on the Actual Conditions of Smoking in Middle and High School Students in One Region (일 지역 중·고등학생의 흡연실태)

  • Kim, Hyeon-Ok
    • Journal of the Korean Society of School Health
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    • v.12 no.1
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    • pp.149-167
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    • 1999
  • To investigate the actual conditions of smoking in middle and high school students in Chinan County, I used a sturctured questionnaire for 1,579 students attending twelve middle-high schools from December 1, 1998 to December 20, 1998. I collected and data correlated the using an $SPSS-PC^+$ 1. The smoking rate of middle-high schoo1 students in Chinan County was 17.9%, relatively high. This smoking rate was different according to the gender, grade, religion, and economic situation. In mals, high school students, non-religious, students low income family students, the smoking rate was higher. The smoking rate of high school students was almost the same as the smoking rate of adults, generally higher than that of foreign teenagers. Because the smoking rat of studinets in the third grade of middle school and in the first grade of high School was six times higher, increased education should be conducted during this time in an attempt to curb the sudden increase of the smoking rate. The smoking rate of girl students was 5.0%; this has increased mor than three times from ten years ago. Consequently, counter measures should be taken against the smoking of female students as well as juvenile smoking in general. In addition, the smoking rate of middle-high school students showed interesting differences when correnated with enviornmental factors. Students with low grades, who are not satisfied with school life, who don't have both parents, who have uncaring parents who nare too strict or too arbitary, who have smoking parents, or who have experienced smoking commonly smoked. Therefore, to lower the smoking rate we should improve the school environment, improve a student's interest in school life. And parents or siblings should lead by example and quit smoking at home. Schools should educate students more effectively concerning the harmful effects of smoking and create an accurate understanding of its dancers. From the beginning, we should teach students never ever to touch cigaretts. 2. The surve discovered that most students started out of curiosity, or solicitantion from friends or elders at middle school, and had been smoking one to five cigarettes for more than a year. They obtained cigarettes at stores and most of them have friends who smoke. As a result anti-smoking education should be conducted at elementary schools prior to middle school. More than 95% of the teenagers who smoke had friends who smote and smoked out of curiosity or the recommendation of elders. Thus, we must focus on teenagers who smoke in group, rather than individually. Fuyrthermore, the strict application of the regulation of tobacco sales as well as tobacco cooperation from retailers are needed. While students did not show any mood or academic achievement difference after beginning smoking, 58.1% of the students a health situdation that was worse. Juvenile smoking is more harmful to the juvenile than adult smoking is to the adult. This should be focused on in an anti-smoking campaign. 3. Students who smoke hada more positive attitude toward smoking than students who don't smoke. Students who smoke had a tendency to have a nuetral position and are not concerned about smoking compared to non-smoking students. The survey showed that the great number of students had a nuetral position. Because this nuetrality may increase Juvenile smoking, education that provides an exact understanding of smoking should be performed to build the correct attidude toward smoking. 4. Middle school students smoke when angry, gloomy, anxious, a lone and when they have some problems to solve, on when they feel inconveniened in other wores, they smoke to reliver stress. They also smok due to addiction. Because smoking is not a praetical method to relieve stress, a program which helps to acquire positive relief stress should be provided to help reduce smoking. 5. About 65% of students who smoke want to quit smoking because of health problem, 78% of them have tried mor than once to quit but failed due to weak will power and peer pressure from friends who smoke. Juvenile smoking is group, oriented. Thus, the program that advances less smoking will be the one that focuseds on groups. 6. As for advice to students who want to quit smoking, "persuasion" was used most commonly, followed by a "presentation on how to quit smoking". Another method were severe punishment. About 70% of the students wanted the anti-smoking guide at school. 7. Most students (73.5%) had a position that more anti-smoking education at school is needed. Obriously, then, anti-smoking education at middle-high schools should be reinfoced. Although the education which explains the harmful influence of tobacco is known as an efficient way prevent smoking; it does not influence students who already smoke. Therefore, for students who smoke, multi-dimensional approaches must be attempted that include physical training, phychokogical approache, consultation and discussion, medical chek-ups, audio-visual education technigues, and professonal instructors, in addition, because smoking students have more negative on lukewarm attitude to anti-smoking education anti-smoking education should be conducted through a communicative style by dedicated teachers who care about students. In order to increase the effectiveness of this program.

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A Study on the Solubilizing and Emulsifying Action of Tocopheryl Acetate using Plant Surfactant (식물성계면활성제를 사용한 토코페릴아세테이트의 가용화와 유화력에 관한 연구)

  • Kim, In-Young;Bae, Bo-Hyeon
    • Journal of the Korean Applied Science and Technology
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    • v.37 no.4
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    • pp.893-905
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    • 2020
  • This study is a study on solubilization and emulsifying power of tocopheryl acetate using vegetable surfactants. High purity polyglyceryl-10 isostearate and polyglyceryl-10 oleate were mixed to synthesize a vegetable surfactant with excellent solubilizing power and emulsifying power. The mixed raw material was named Solubil EWG-1100. The appearance of this raw material was a pale yellowish paste with a specific smell, specific gravity of 1.12, and acid value of 0.085. The HLB value of this surfactant was calculated by the Griffin's equation with an average value of 15.17. The behavior of this surfactant to solubilize tocopheryl acetate was mechanically verified. The performance of solubilization was evaluated by a method of visual evaluation and was measured by a transmittance rate at 650 nm using a UV spectrophotometer. As a result, in the formulation using 3% ethanol as a co-solvent, the concentration of surfactant was required to solubilize tocopheryl acetate was required about 5 times of natural surfactant. In the formulation without ethanol as a co-solvent, the concentration of surfactant was required to solubilize tocopheryl acetate required about 7 times of natural surfactant. In addition, the concentration of surfactant required to make an emulsifivation 10 % of tocopheryl acetate was 1 wt% of Solubil EWG-1100, and the emulsified particle size was 3.5 mm in cream formula. In order to obtain stable and fine emulsified particles, it was found that as the concentration of tocopheryl acetate increased, the concentration of Solubil EWG-1100 also was to increase. As a result of testing the solubilizing power of the surfactant according to the pH various change, it showed stable solubilizing power in the acidic region of pH=3.2, the neutral region of pH=7.0, and the alkaline region of pH=11.8. As application, based on these results, it is expected that it can be widely applied to the cosmetics field that develops skin care prescriptions, sensitive skin products, and heavy dry skin products.

Macro-environmental Drivers and Technological Evolution of Complex Product System: Evidence from Nuclear Power Plant (거시환경요인과 복합제품시스템의 기술진화: 원자력 발전 플랜트의 사례를 중심으로)

  • Kwak, Kiho;Kim, Wonjoon;Kim, Minki;Cho, Chang Yeon
    • Journal of Technology Innovation
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    • v.25 no.2
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    • pp.89-125
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    • 2017
  • Complex product systems (CoPs) is a engineering-intensive products with high-ended design technology, which are closely linked with national economic growth and development of social infrastructures. Accordingly, in order to understand the technological evolution of CoPs, it is necessary to identify the macro-environmental drivers surrounding the CoPs and their impact on the technological evolution of the CoPS. Therefore, we investigate the effect of policy, economic and social drivers on the technological evolution of CoPS by implementing the longitudinal case study on nuclear power plant during the periods between 1950 and 2010s. Based on the analysis of various sources of secondary data and primary data through interviews, we found that the technological evolution of nuclear power plant is progressed as "Phase 1: Application research for peaceful utilization of nuclear energy" between 1950s and 1960s, "Phase 2: The first renaissance of nuclear energy" during 1970s, "Phase 3: Enhancement of safety and the catch-up of latecomers in nuclear energy" between 1990s and 2000s, and "Phase 4: Top prioritization of safety and the development of next generation reactors for the second renaissance of nuclear energy" since 2010s. We also found that various kinds of policy, economic and social drivers, such as energy policy, investment in technology development, economic growth and energy demand, social acceptability and environmental concern, have affected the technology evolution of nuclear power plant at each phase. We emphasize the role of macroenvironmental drivers in the technological evolution of CoPS. We also suggest that countries that endeavor to develop CoPs need to utilize those drivers for enhancing competitiveness and sustaining leadership.