• Title/Summary/Keyword: energy generation

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Genetic Variation Analysis of Early-heading Plant (Oryza sativa L.) Lines Derived from Gamma-ray Irradiation (방사선조사 유래의 조기출수 식물(Oryza sativa L.) 계통의 유전적 변이 분석)

  • Ryu, Jai-Hyunk;So, Hyun-Su;Lyu, Jae-Il;Kwon, Oh-Do;Lee, Young-Il;Jin, Il-Doo;Lee, Hyo-Yeon;Bae, Chang-Hyu
    • Korean Journal of Plant Resources
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    • v.25 no.1
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    • pp.142-151
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    • 2012
  • This study was carried out to evaluate genetic variation of early-heading rice (Oryza sativa L. cv. Dongjin 1) lines derived from gamma-ray ($^{60}Co$, 300 Gy) irradiation. The average heading date of the 5 early-heading lines in $M_7$ and $M_8$ generation was faster than that of untreated control as 11 (line ${\gamma}$-2), 10 (line ${\gamma}$-5), 6 (${\gamma}$-1 line), 5 (${\gamma}$-3) and 4 days (line ${\gamma}$-4), respectively. According to ISSR analysis, polymorphic rate of the early-heading lines (from 5.9% to 23.4%) was higher than that of control (4.3%). The result indicates that the gamma-ray promote variation at DNA level. When genetic variations of rps16-trnK region were evaluated by nucleotide analysis, nucleotide length of the rps16-trnK region was 664 bp in all the early-heading lines and control. Out of 5 sites of nucleotide transposition detected in the region, however, 2 sites were appeared only in the early-heading lines.

Gamma Radiation Sensitivity and Quantitative Characters in M1 Generation of Heteropappus hispidus (Thunb.) (갯쑥부쟁이(Heteropappus hispidus (Thunb.))의 감마방사선 감수성과 M1 세대 형질변동 특징)

  • Oh, Byung-Kwon;Hong, Kyung-Ae;Song, Sung-Jun;Lee, Sun-Joo;Lee, Young-Il;U., Zang-Kual
    • Korean Journal of Environmental Agriculture
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    • v.22 no.4
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    • pp.294-299
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    • 2003
  • The seeds of naturally growing Heteropappus hispidus (Thunb.) were treated by nine different doses (0, 10, 20, 40, 80, 120, 160, 200, 300, 400 Gy) of gamma rays to investigate their germination rate and to quantity the characteristics of their germinated plants as like as leaf appearance and length, the formation rate of anthocyanin color in stem 30 days after germination, the formation rate of rosette leaf and multi-shoot, the flowering and seed-bearing, and shoot length. The germination rate at least up to 120Gy was not greatly affected but was rapidly decreased at over 160Gy. It seemed that lethal dose ($LD_{50}$) of germination was 160Gy. The leaf appearance and growth was also inhibited, but the formation rate of anthocyanin color in the flower stem was enhanced up to 30% with dose. The rosette plants were observed in plants irradiated with higher than 40Gy. Multi-shoots were developed over 80Gy. For a short shoot length and bundle of thin stem, it was considered that they can be selected as the potential pot flower plants, through genetic fixation. In particular, it was suggested that the formation of anthocyanin color in flower stem, rosette and multi-shoot plants induced by the high dose of gamma rays could be utilized as the morphological markers for the mutant selection of Heteropappus hispidus (Thunb.).

Associations of the Porcine Melanocortin-4 Receptor (MC4R) Gene with Growth Traits in Duroc Pigs (듀록 품종의 Melanocortin-4 Receptor(MC4R) 유전자와 성장형질과의 연관성 분석)

  • Cho, K.H.;Kim, M.J.;Choi, B.H.;Jeon, G.J.;Ryu, J.W.;Jung, H.J.;Kim, I.C.;Lee, H.K.;Jeon, G.J.
    • Journal of Animal Science and Technology
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    • v.49 no.4
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    • pp.437-442
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    • 2007
  • The melanocortin-4 receptor(MC4R) is virtually expressed in all brain regions and plays an important role in energy homeostasis in mammals. MC4R has been intensively studied as a trait gene controlling economically important traits, such as growth and feed conversion, etc. Six hundreds and sixty Duroc pigs were genotyped for the MC4R locus and analyzed their relationships with breeding values for average daily gain(ADG), backfat thickness(BF), days to 90kg(D90) and feed conversion(FC). The estimated genotype frequencies for the all Duroc pigs were: 30.8%, 45.2%, 24.1% for AA, AB and BB genotypes, respectively. The mutant A allele was significantly associated with ADG, D90 and BF whereas no significant relationship was found with FC. The change of gene frequencies by generation was shown in both selected and culled groups. These results indicate that the MC4R polymorphism could be integrated in the present selection program to realize a marker-assisted selection for the growth traits of the Duroc population.

Analysis of Factors Affecting the Hygroscopic Performance of Thermally Treated Pinus koraiensis Wood (잣나무열처리재의 흡방습성능에 미치는 영향인자 분석)

  • Chang, Yoon-Seong;Han, Yeon-Jung;Eom, Chang-Deuk;Park, Joo-Saeng;Park, Moon-Jae;Choi, In-Gyu;Yeo, Hwan-Myeong
    • Journal of the Korean Wood Science and Technology
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    • v.40 no.1
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    • pp.10-18
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    • 2012
  • A high airtightness is required for the residential spaces constructed recently to save cooling and heating energy through improving insulation performance. Because the chances to release steam formed by human activity in building and inflow of water vapor in outdoor air to residential space are reduced, the natural humidity control performance of interior materials has become more important. In this study, hygroscopic performance of thermo-physically treated wood (Pinus koraiensis) was estimated. At various relative humidity condition, the water vapor adsorption and desorption rates of wooden materials were measured as well as equilibrium moisture content. Effects of roughness and surface microstructure as physical factors and functional groups as chemical factors on the hygroscopicity were analyzed. It is expected that the results from this study and further study of measuring moisture generation in residential spaces could contribute to install a system for evaluating the hygrothermal performance of wooden building.

Developing an Early Leakage Detection System for Thermal Power Plant Boiler Tubes by Using Acoustic Emission Technology (음향방출법을 이용한 발전용 보일러 튜브 미세누설 조기 탐지 시스템 개발 및 성능 검증)

  • Lee, Sang Bum;Roh, Seon Man
    • Journal of the Korean Society for Nondestructive Testing
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    • v.36 no.3
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    • pp.181-187
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    • 2016
  • A thermal power plant has a heat exchanger tube to collect and convert the heat generated from the high temperature and pressure steam to energy, but the tubes are arranged in a complex manner. In the event that a leakage occurs in any of these tubes, the high-pressure steam leaks out and may cause the neighboring tubes to rupture. This leakage can finally stop power generation, and hence there is a dire need to establish a suitable technology capable of detecting tube leaks at an early stage even before it occurs. As shown in this paper, by applying acoustic emission (AE) technology in existing boiler tube leak detection equipment (BTLD), we developed a system that detects these leakages early enough and generates an alarm at an early stage to necessitate action; the developed system works better that the existing system used to detect fine leakages. We verified the usability of the system in a 560MW-class thermal power plant boiler by conducting leak tests by simulating leakages from a variety of hole sizes (ⵁ2, ⵁ5, ⵁ10 mm). Results show that while the existing fine leakage detection system does not detect fine leakages of ⵁ2 mm and ⵁ5 mm, the newly developed system could detect leakages early enough and generate an alarm at an early stage, and it is possible to increase the signal to more than 18 dB.

Evaluations of Si based ternary anode materials by using RF/DC magnetron sputtering for lithium ion batteries

  • Hwang, Chang-Muk;Park, Jong-Wan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.302-303
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    • 2010
  • Generally, the high energy lithium ion batteries depend intimately on the high capacity of electrode materials. For anode materials, the capacity of commercial graphite is unlike to increase much further due to its lower theoretical capacity of 372 mAhg-1. To improve upon graphite-based negative electrode materials for Li-ion rechargeable batteries, alternative anode materials with higher capacity are needed. Therefore, some metal anodes with high theoretic capacity, such as Si, Sn, Ge, Al, and Sb have been studied extensively. This work focuses on ternary Si-M1-M2 composite system, where M1 is Ge that alloys with Li, which has good cyclability and high specific capacity and M2 is Mo that does not alloy with Li. The Si shows the highest gravimetric capacity (up to 4000mAhg-1 for Li21Si5). Although Si is the most promising of the next generation anodes, it undergoes a large volume change during lithium insertion and extraction. It results in pulverization of the Si and loss of electrical contact between the Si and the current collector during the lithiation and delithiation. Thus, its capacity fades rapidly during cycling. Si thin film is more resistant to fracture than bulk Si because the film is firmly attached to the substrate. Thus, Si film could achieve good cycleability as well as high capacity. To improve the cycle performance of Si, Suzuki et al. prepared two components active (Si)-active(Sn, like Ge) elements film by vacuum deposition, where Sn particles dispersed homogeneously in the Si matrix. This film showed excellent rate capability than pure Si thin film. In this work, second element, Ge shows also high capacity (about 2500mAhg-1 for Li21Ge5) and has good cyclability although it undergoes a large volume change likewise Si. But only Ge does not use the anode due to its costs. Therefore, the electrode should be consisted of moderately Ge contents. Third element, Mo is an element that does not alloys with Li such as Co, Cr, Fe, Mn, Ni, V, Zr. In our previous research work, we have fabricated Si-Mo (active-inactive elements) composite negative electrodes by using RF/DC magnetron sputtering method. The electrodes showed excellent cycle characteristics. The Mo-silicide (inert matrix) dispersed homogeneously in the Si matrix and prevents the active material from aggregating. However, the thicker film than $3\;{\mu}m$ with high Mo contents showed poor cycling performance, which was attributed to the internal stress related to thickness. In order to deal with the large volume expansion of Si anode, great efforts were paid on material design. One of the effective ways is to find suitably three-elements (Si-Ge-Mo) contents. In this study, the Si based composites of 45~65 Si at.% and 23~43 Ge at.%, and 12~32 Mo at.% are evaluated the electrochemical characteristics and cycle performances as an anode. Results from six different compositions of Si-Ge-Mo are presented compared to only the Si and Ge negative electrodes.

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Independent I/O Relay Class Design Using Modbus Protocol for Embedded Systems

  • Kim, Ki-Su;Lee, Jong-Chan
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.6
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    • pp.1-8
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    • 2020
  • Communication between system modules is applied using the Modbus protocol in industrial sites including smart factories, industrial drones, building energy management systems, PLCs, ships, trains, and airplanes. The existing Modbus was used for serial communication, but the recent Modbus protocol is used for TCP/IP communication.The Modbus protocol supports RTU, TCP and ASCII, and implements and uses protocols in embedded systems. However, the transmission I/O devices for RTU, TCP, and ASCII-based protocols may differ. For example, RTU and ASCII communications transmit on a serial-based communication protocol, but in some cases, Ethernet TCP/IP transmission is required. In particular, since the C language (object-oriented) is used in embedded systems, the complexity of source code related to I/O registers increases. In this study, we designed software that can logically separate I/O functions from embedded devices, and designed the execution logic of each instance requiring I/O processing through a delegate class instance with Modbus RTU, TCP, and ASCII protocol generation. We designed and experimented with software that can separate communication I/O processing and logical execution logic for each instance.

Development of FCEV accident scenario and analysis study on dangerous distance in road tunnel (도로터널에서 수소차 사고시나리오 개발 및 위험거리에 대한 분석 연구)

  • Lee, Hu-Yeong;Ryu, Ji-Oh
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.24 no.6
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    • pp.659-677
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    • 2022
  • Hydrogen is emerging as a next-generation energy source and development and supply of FCEV (hydrogen fuel cell electric vehicle) is expected to occur rapidly. Accordingly, measures to respond to hydrogen car accidents are required and researches on the safety of hydrogen cars are being actively conducted. In this study, In this study, we developed a hydrogen car accident scenarios suitable for domestic conditions for the safety evaluation of hydrogen car in road tunnels through analysis of existing experiments and research data and analyzed and presented the hazard distance according to the accident results of the hydrogen car accident scenarios. The accident results according to the hydrogen car accident scenario were classified into minor accidents, general fires, jet flames and explosions. The probability of occurrence of each accident results are predicted to be 93.06%, 1.83%, 2.25%, and 2.31%. In the case of applying the hydrogen tank specifications of FCEV developed in Korea, the hazard distance for explosion pressure (based on 16.5 kPa) is about 17.6 m, about 6 m for jet fire, up to 35 m for fireball in road tunnel with a standard cross section (72 m2).

Modified Empirical Formula of Dynamic Amplification Factor for Wind Turbine Installation Vessel (해상풍력발전기 설치선박의 수정 동적증폭계수 추정식)

  • Ma, Kuk-Yeol;Park, Joo-Shin;Lee, Dong-Hun;Seo, Jung-Kwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.6
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    • pp.846-855
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    • 2021
  • Eco-friendly and renewable energy sources are actively being researched in recent times, and of shore wind power generation requires advanced design technologies in terms of increasing the capacities of wind turbines and enlarging wind turbine installation vessels (WTIVs). The WTIV ensures that the hull is situated at a height that is not affected by waves. The most important part of the WTIV is the leg structure, which must respond dynamically according to the wave, current, and wind loads. In particular, the wave load is composed of irregular waves, and it is important to know the exact dynamic response. The dynamic response analysis uses a single degree of freedom (SDOF) method, which is a simplified approach, but it is limited owing to the consideration of random waves. Therefore, in industrial practice, the time-domain analysis of random waves is based on the multi degree of freedom (MDOF) method. Although the MDOF method provides high-precision results, its data convergence is sensitive and difficult to apply owing to design complexity. Therefore, a dynamic amplification factor (DAF) estimation formula is developed in this study to express the dynamic response characteristics of random waves through time-domain analysis based on different variables. It is confirmed that the calculation time can be shortened and accuracy enhanced compared to existing MDOF methods. The developed formula will be used in the initial design of WTIVs and similar structures.

Microfluidic Assisted Synthesis of Ag-ZnO Nanocomposites for Enhanced Photocatalytic Activity (광촉매 성능 강화를 위한 미세유체공정 기반 Ag-ZnO 나노복합체 합성)

  • Ko, Jae-Rak;Jun, Ho Young;Choi, Chang-Ho
    • Clean Technology
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    • v.27 no.4
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    • pp.291-296
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    • 2021
  • Recently, there has been increasing demand for advancing photocatalytic techniques that are capable of the efficient removal of organic pollutants in water. TiO2, a representative photocatalytic material, has been commonly used as an effective photocatalyst, but it is rather expensive and an alternative is required that will fulfill the requirements of both high performing photocatalytic activities and cost-effectiveness. In this work, ZnO, which is more cost effective than TiO2, was synthesized by using a microreactor-assisted nanomaterials (MAN) process. The process enabled a continuous production of ZnO nanoparticles (NPs) with a flower-like structure with high uniformity. In order to resolve the limited light absorption of ZnO arising from its large band gap, Ag NPs were uniformly decorated on the flower-like ZnO surface by using the MAN process. The plasmonic effect of Ag NPs led to a broadening of the absorption range toward visible wavelengths. Ag NPs also helped inhibit the electron-hole recombination by drawing electrons generated from the light absorption of the flower-like ZnO NPs. As a result, the Ag-ZnO nanocomposites showed improved photocatalytic activities compared with the flower-like ZnO NPs. The photocatalytic activities were evaluated through the degradation of methylene blue (MB) solution. Scanning electron microscopy (SEM), x-ray diffraction (XRD), and energy-dispersive x-ray spectroscopy (EDS) confirmed the successful synthesis of Ag-ZnO nanocomposites with high uniformity. Ag-ZnO nanocomposites synthesized via the MAN process offer the potential for cost-effective and scalable production of next-generation photocatalytic materials.