• Title/Summary/Keyword: TMA

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Fabrication and Characteristics of ZnO-based thin film sensors with high selectivity for TMA gas (TMA 가스 선택성 향상을 위한 ZnO계 박막센서의 제작 및 특성)

  • Park, Sung-Hyun;Choi, Woo-Chang;Kim, Sung-Woo;Ryu, Jee-Youl;Choi, Hyek-Hwan;Lee, Myong-Kyo;Kwon, Tae-Ha
    • Journal of Sensor Science and Technology
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    • v.9 no.1
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    • pp.36-43
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    • 2000
  • In oder to enhance the selectivity of TMA(trimethylamine) gas, the ZnO-based films which were doped with $Al_2O_3$, $TiO_2, $In_2O_3$ and $V_2O_5$ catalysts with various weight percents were deposited in oxygen by RF magnetron sputtering method. To improve electrical stability of sensors, the ZnO-based films were annealed in oxygen at $700^{\circ}C$ for 1 hour. The TMA selectivity of sensors was defined by the magnitude($S_{TMA}/S_{DMA}$ and $S_{TMA}/S_{NH3}$) of TMA sensitivity relative to DMA and sensitivity ammonia($NH_3$) sensitivity, respectively. The $ZnO+Al_2O_3(4\;wt.%)+TiO_2(1\;wt.%)+In_2O_3(1\;wt.%)$ sensor showed high $S_{TMA}/S_{DMA}$ of 5.9 and $S_{TMA}/S_{NH3}$ of 26 to 160 ppm at the working temperature of $300^{\circ}C$ respectively.

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Changes in Amine Constituents of Kwamaege Flesh by Different Drying for Pacific Saury, Cololabis saira (꽁치과메기의 건조조건에 따른 Amine의 변화)

  • 오승희;김덕진;최경호
    • The Korean Journal of Food And Nutrition
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    • v.11 no.1
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    • pp.20-25
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    • 1998
  • We investigated a DMA, TMA, TMAO, a toxic substance to human body can be generated during drying, in a Pacific saury, Cololabis saira. Changes of amine during drying showed a rapid increasing trend until a day of ninth according to an increasing of ambient temperature. And a content of DMA, TMA, TMAO during artificial drying is lowerd than during natural drying. A case of TMAO contents showed that it was decrease during TMA component is generated in drying process Also they can be generated in a drying process. Thus we concluded that an approvement in a general distribution of Kwamaege is needed for preventing a generation of a toxic component such as a DMA, TMA.

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A Study on the Development and of Establishment Performance Evaluation Criteria of Working Truck Mounted Attenuator (작업차량 장착용 충격흡수장치(TMA) 성능평가기준 수립 및 개발 연구)

  • Joo, Jae-Woong;Jang, Dae-Young;Park, Je-Jin
    • Journal of the Korean Society of Safety
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    • v.27 no.6
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    • pp.185-191
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    • 2012
  • Rear collisions to expressway work trucks result many casualties these days. But, currently, no special measure are being taken except deploying sign trucks behind the working trucks. In the U.S and Europe, trucks with TMA(Truck Mounted Attenuator) are being deployed behind the working truck, which is regarded as the standard method for work area safety, thereby reducing the fatality rates and property damage tremendously. Also, standard for the performance of TMA are established and TMA can be used in the field only when it satisfies the standard. In Korea, neither the standard for nor any guide to the TMA exists. In the situation some manufacturer developed TMA without proper performance evaluation and marketed limited number of TMAs in the field. In the study, NCHRP350, which is the performance standard of expressway safety features of U.S. and materials related to the TMA standard in Europe have been reviewed to establish the Korean performance criteria. Based on the review, and incorporating existing Korean standard for crash cushions, domestic standard for TMA has been proposed and applied in developing Korean TMA and crash tested it to verify the performance. The original design developed was crash tested and modified. The newly proposed design was studied using impact simulation program several times. Modifications were made after each simulation and prototype was built and crash tested as per the newly established TMA performance criteria.

The Improvement of Target Motion Analysis(TMA) for Submarine with Data Fusion (정보융합 기법을 활용한 잠수함 표적기동분석 성능향상 연구)

  • Lim, Young-Taek;Ko, Soon-Ju;Song, Taek-Lyul
    • Journal of the Korea Institute of Military Science and Technology
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    • v.12 no.6
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    • pp.697-703
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    • 2009
  • Target Motion Analysis(TMA) means to detect target position, velocity and course for using passive sonar system with bearing-only measurement. In this paper, we apply the TMA algorithm for a submarine with Multi-Sensor Data Fusion(MSDF) and we will decide the best TMA algorithm for a submarine by a series of computer simulation runs.

Measurements of Trimethylamine (TMA) in air by Tedlar bag sampling and SPME analysis (환경대기 중 Trimethylamine (TMA)의 측정: Tedlar bag 방식의 채취와 SPME 분석법의 특성 연구)

  • Kim, K.H.;Hyum, S.H.;Im, M.S.
    • Analytical Science and Technology
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    • v.19 no.1
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    • pp.96-102
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    • 2006
  • Trimethylamine (TMA) is one of the difficult odorous compounds for the collection and analysis. Although sulfuric acid absorption and/or sulfuric acid impregnated filter method are commonly recommended for its sampling, these methods also suffer from difficulties involved in sample treatment and operational procedures. Hence, as an ancillary approach to measure TMA, we investigated the combination of bag sampling and SPME analysis for TMA measurements. For the purpose of our study, we investigated the following three subjects: 1) temporal variability of standard storage, 2) bag loss effect of TMS, and 3) TMA loss due to repetitive analysis of an identical bag sample. According to our storage test up to 7 or 20 dyas, TMA loss were found to occur up to 40 to 50% within relatively short period of up to 48 hrs depending on its concentration ranges. When the tests were made for bag loss by transferring TMA standards across different size bags, we were able to find that the extent of bag loss are not significant with 5 to 20% loss rate. Finally, the TMA sorptive loss via its exposure to SPME fiber was generally estimated to run from 2 to 3%.

A Study on the Transaction Matching Application and Major BPO Business Scenarios (TMA의 운용과 주요 BPO 비즈니스 시나리오에 관한 연구)

  • CHAE, Jin-Ik
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.65
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    • pp.117-139
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    • 2015
  • The BPO is an irrevocable undertaking given by an obligor bank to a recipient bank to pay a specified amount under the condition of a successful electronic matching of data or acceptance of mismatches. The BPO enables the participating banks to provide sellers and buyers with enhanced financing services. Therefore, BPO gives banks the tools to provide them with guarantees and other multi-banking services. All the participating banks must use the same Transaction Matching Application(TMA) for BPO business. In order to exchange BPO-related data, banks must be subscribed to the same TMA scheme. Participation in the TMA scheme is limited to banks only. The TMA is matching and workflow application as instrument to determine whether to pay the BPO or not. Therefore, TMA will have an important role to play in the business of the BPO. So, This paper is to review the mechanism of a TMA and the major business scenarios in Banking Payment Obligation Transactions. In Particular, it has been included the exchange and matching of data messages, the disposal of discrepancies, document payment and others based on URBPO. This study will be based on documentary research including swift com and icc.org and so on.

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Target Motion Analysis for a Passive Sonar System with Observability Enhancing (가관측성 향상을 통한 수동소나체계의 표적기동 분석)

  • 한태곤;송택렬
    • The Journal of the Acoustical Society of Korea
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    • v.18 no.6
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    • pp.9-16
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    • 1999
  • As a part of target motion analysis(TMA) with highly noisy bearings-only measurements from a passive sonar system, a nonlinear batch estimator is proposed to provide the initial estimates to a sequential estimator called the modified gain extended Kalman filter(MGEKF). Based on the system observability analysis of passive target tracking, a practical and effective method is suggested to determine the observer maneuvers for improved TMA performance through system observability enhancing. Also suggested is a method to determine observer location for enhanced system observability at the initial phase of TMA from various engagement boundaries which represent the relationship between observer-target relative geometrical data and system observability. The proposed TMA methods are tested by a series of computer simulation runs.

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The Study on Cooling Characterics of TMA Clathrate with Ethanol (에탄올을 첨가한 TMA 포접화합물의 냉각특성에 대한 연구)

  • 김창오;김진흥;정낙규;김석현
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.14 no.8
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    • pp.634-640
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    • 2002
  • The purpose of this study is to investigate the propriety of TMA clathrate as a cold storage medium. Particularly, this is to examine the extent of subcooling improvement when the additives is added to the TMA clathrate, because water used for cold storage ma terial has low phase change temperature and subcooling. This study has been analyzed and compared pure water with TMA 30 wt% clathrate how phase change temperature, subcooling and specific heat in the various concentrations are changed. This results prove low phase change temperature and subcooling control effect when the ethanol is added to the TMA 30 wt% clathrate than the TMA 30 wt% clathrate. In addition, it results low specific heat when there is added to the TMA 30 wt% clathrate over 0.5 wt% ethanol in the cold heat source temperature under $-7^{\circ}C$. The other side, it results high specific heat when the ethanol is added in it at the cold heat source temperature under $-5^{\circ}C$. Therefore, it is found that the additive must be controlled by available solution limit and study for new additive must be lasted to know its effect.

Reduction of Trimethylamine Off-Odor by Lactic Acid Bacteria Isolated from Korean Traditional Fermented Food and Their In Situ Application

  • Park, Seul-Ki;Jo, Du-Min;Yu, Daeung;Khan, Fazlurrahman;Lee, Yang Bong;Kim, Young-Mog
    • Journal of Microbiology and Biotechnology
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    • v.30 no.10
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    • pp.1510-1515
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    • 2020
  • Trimethylamine (TMA) is a well-known off-odor compound in fish and fishery products and is a metabolic product of trimethylamine N-oxide (TMAO) generated by the enzymatic action of microorganisms. The off-odor is a factor that can debase the value of fish and fishery products. The present study aimed to remove TMA using lactic acid bacteria (LAB). A total of fifteen isolates exhibiting the TMA reduction efficacy were isolated from Korean traditional fermented foods. Among these isolates, five LAB isolates (Lactobacillus plantarum SKD 1 and 4; Lactobacillus paraplantarum SKD 15; Pediococcus stilesii SKD 11; P. pentosaceus SKD 14) were selected based on their high TMA reduction efficacy. In situ reduction of TMA efficacy by the LAB cell-free supernatant was evaluated using a spoiled fish sample. The results showed effective TMA reduction by our selected strains: SKD1 (45%), SKD4 (62%), SKD11 (60%), SKD14 (59%), and SKD15 (52%), respectively. This is the first study on TMA reduction by the metabolic activity of LAB and in situ reduction of TMA using cell-free supernatant of LAB. The present finding suggests an economically useful and ecofriendly approach to the reduction of TMA.

The Study on Improvement in Subcooling of TMA Clathrate for PCM in Ice Storage System (빙축열시스템 PCM용 TMA-포접화합물의 과냉도 개선에 대한 연구)

  • Kim, J.H.;Chung, N.K.;Kim, C.O.
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.1663-1666
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    • 2003
  • TMA clathrate that is used by PCM of ice storage system in this research creates hydrate crystallization at higher temperature than pure water, and application is expected as PCM because having comparative big dormant temperature without phase separation phenomenon. In case this research uses TMA clathrate by PCM, choose admixture by purpose to control or remove subcooling of TMA clathrate and evaluated experimentally. Subcooling is improved and can expect contraction of freezing machine running time and increase of coefficient of performance as that add admixture to TMA clathrate conclusively. Also, may supply thermal storage system that apply low temperature potential heat thermal storage material that subcooling is improved more extensively laying stress on medium size building and small size building, can expect allowance through localization of ice storage system.

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