• 제목/요약/키워드: TEO

검색결과 277건 처리시간 0.023초

SPEEK/PWA/Silica 복합막의 전기화학적 특성에 관한 연구 (A Study on the Electrochemical Properties of SPEEK/PWA/Silica Composite Membranes)

  • 오세중
    • 한국산학기술학회논문지
    • /
    • 제14권5호
    • /
    • pp.2529-2535
    • /
    • 2013
  • SPEEK/PWA/silica 전해질 복합막을 제조하기 위하여 졸-겔 방법을 이용하였다. 졸-겔반응의 전구체로는 TEOS를 사용하였으며 첨가제 겸 촉매로는 phosphotungstic acid(PWA)를 사용하였다. FE-SEM 분석을 통하여 PWA 및 silica 나노입자들은 고분자속으로 균일하게 분산되는 것을 확인할 수 있었다. SPEEK/PWA/silica 복합막의 함수율은 TEOS의 비율이 낮은 경우에는 TEOS의 증가에 따라 함수율이 감소하였지만 TEOS의 비율이 높은 경우에는 TEOS의 영향을 적게 받았다. SPEEK/PWA/silica 복합막의 이온전도도는 함수율의 변화와 유사한 경향을 나타내었으며 TEOS의 비율이 증가함에 따라 처음에는 이온전도도가 감소하다가 다시 증가하는 경향을 나타내었다. SPEEK/PWA/silica 복합막의 메탄올 투과도는 TEOS의 농도가 증가함에 따라 투과도가 감소하는 경향을 나타내었다.

Chemopreventive Activity of Turmeric Essential Oil and Possible Mechanisms of Action

  • Liju, Vijayasteltar Belsamma;Jeena, Kottarapat;Kuttan, Ramadasan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권16호
    • /
    • pp.6575-6580
    • /
    • 2014
  • This study aimed to evaluate the antimutagenic and anticarcinogenic activity of turmeric essential oil as well as to establish biochemical mechanisms of action. Antimutagenicity testing was accomplished using strains and known mutagens with and without microsomal activation. Anticarcinogenic activity was assessed by topical application of 7, 12 - dimethylbenz[a]anthracene (DMBA) as initiator and 1% croton oil as promoter for the induction of skin papillomas in mice. Inhibition of p450 enzymes by TEO was studied using various resorufins and aminopyrene as substrate. Turmeric essential oil (TEO) showed significant antimutagenic activity (p<0.001) against direct acting mutagens such as sodium azide ($NaN_3$), 4-nitro-O-phenylenediamine (NPD) and N-methyl-N-nitro N'nitrosoguanine (MNNG). TEO was found to have significant antimutagenic effect (>90%) against mutagen needing metabolic activation such as 2-acetamidoflourene (2-AAF). The study also revealed that TEO significantly inhibited (p<0.001) the mutagenicity induced by tobacco extract to Salmonella TA 102 strain. DMBA and croton oil induced papilloma development in mice was found to be delayed and prevented significantly by TEO application. Moreover TEO significantly (P<0.001) inhibited isoforms of cytochrome p450 (CYP1A1, CYP1A2, CYP2B1/2, CYP2A, CYP2B and CYP3A) enzymes in vitro, which are involved in the activation of carcinogens. Results indicated that TEO is antimutagenic and anticarcinogenic and inhibition of enzymes (p450) involved in the activation of carcinogen is one of its mechanisms of action.

전통 상류주택 안채의 측면 툇마루에 관한 연구 (The study on the Side-TeoMaru of An-Chae(Inner Quter) of upper-class houses in traditional residence.)

  • 김난아;백영흠
    • 한국주거학회:학술대회논문집
    • /
    • 한국주거학회 2000년도 학술발표대회논문집
    • /
    • pp.75-78
    • /
    • 2000
  • This study purpose that researching Side- TeoMaru of upper-class houses in traditional An-Chae space and researching regional characteristics. Side-TeoMaru type is An-Bang and Gunner-Bang. That is found Chungchong-Do, Cholla-Do, Kyongsangnam-Do. I found different distribution in this region. This study has researched by measurement and personal interview.

  • PDF

전기철도차량 이선 현상 검측을 위한 TEO 및 STFT 신호처리기법 적용에 관한 연구 (A Study on the Application of TEO and STFT Signal Processing Techniques for Detection of Electric Railway Contact Loss)

  • 정노건;박철민;이재범;박영;신승권
    • 전기학회논문지
    • /
    • 제67권11호
    • /
    • pp.1530-1535
    • /
    • 2018
  • In this paper, A technique for detecting contact loss at the input power of a railway vehicle has been studied when the contact loss occurs in the feed system. The impedance of the actual railway line was applied to the modeling of the feed system, and modeling was performed based on the performance of the electric railway vehicle. The input voltage and current of the railway vehicle through modeling were analyzed by applying TEO and STFT signal processing technique.

An Applicability of Teager Energy Operator and Energy Separation Algorithm for Waveform Distortion Analysis : Harmonics, Inter-harmonics and Frequency Variation

  • Cho, Soo-Hwan;Hur, Jin;Chung, Il-Yop
    • Journal of Electrical Engineering and Technology
    • /
    • 제9권4호
    • /
    • pp.1210-1216
    • /
    • 2014
  • This paper deals with an application of Teager Energy Operator (TEO) and Energy Separation Algorithm(ESA) to detect and determine various voltage waveform distortions like harmonics, inter-harmonics and frequency variation. Because the TEO and DESA algorithm was initially proposed for speech or communication analysis, its applications are limited to some types of waveform in the power quality analysis area. For example, an undistorted voltage signal is similar with a pure sinusoid. A voltage fluctuation is very similar with an amplitude-modulated signal, from the viewpoint of signal theory. And a continuous frequency variation is similar with a frequency-modulated signal, which is also known as a chirp signal. This paper is written to show that the TEO and DESA algorithm can be used for detecting occurrences of the representative waveform distortions and determining their instantaneous information of amplitude and frequency.

Improved Melody Recognition Performance of a Cochlear Implant Speech Processing Strategy Using Instantaneous Frequency Encoding Based on Teager Energy Operator

  • Choi, Sung-Jin;Ryu, Sang-Baek;Kim, Kyung-Hwan
    • 대한의용생체공학회:의공학회지
    • /
    • 제31권6호
    • /
    • pp.417-426
    • /
    • 2010
  • We present a speech processing strategy incorporating instantaneous frequency (IF) encoding for the enhancement of melody recognition performance of cochlear implants. For the IF extraction from incoming sound, we propose the use of a Teager energy operator (TEO), which is advantageous for its lower computational load. From time-frequency analysis, we verified that the TEO-based method provides proper IF encoding of input sound, which is crucial for melody recognition. Similar benefit could be obtained also from the use of a Hilbert transform (HT), but much higher computational cost was required. The melody recognition performance of the proposed speech processing strategy was compared with those of a conventional strategy using envelope extraction, and the HT-based IF encoding. Hearing tests on normal subjects were performed using acoustic simulation and a musical contour identification task. Insignificant difference in melody recognition performance was observed between the TEO-based and HT-based IF encodings, and both were superior to the conventional strategy. However, the TEO-based strategy was advantageous considering that it was approximately 35% faster than the HT-based strategy.

TEO&DESA를 활용한 Auto-synchronizer의 전압 파라미터 측정에 관한 연구 (A Study on Measurement of Voltage Parameters using TEO&DESA in Auto-synchronizer)

  • 신훈철;한수경;유준수;조수환
    • 전기학회논문지
    • /
    • 제67권7호
    • /
    • pp.816-823
    • /
    • 2018
  • The Auto-synchronizer is essential equipment for synchronizing a generator to the power system. It is performing that measurement of the magnitude, frequency and phase of the voltage signal of the power system and generator. It is important to select the appropriate measurement algorithm for preventing various problem such as mechanical stress and Electrical problem. Teager Energy Operator(TEO) and Discrete separation algorithm(DESA) is measurable the instantaneous parameters of a sine wave using 5 samples and can be measured at a fast and with a simple operation. Therefore it has many advantages in measuring the parameters. In this paper, it confirmed measurement results using matlab simulations when there are synchronized in order of frequency, magnitude. Also it presented methods using digital filters and sample intervals to improve accuracy.

HornePNA v2.0 프리앰블 패턴에 적합한 버스트 신호 검출 알고리즘 (Burst Signal Detecting Algorithm for HomePNA v2.0 Preamble Pattern)

  • 김경덕;황성현;최형진
    • 한국통신학회논문지
    • /
    • 제26권11A호
    • /
    • pp.1848-1857
    • /
    • 2001
  • 이 논문에서는 TEO 알고리즘에 기반한 ETEO와 MTEO 버스트 신호 검출 알고리즘이 제안되었다. 이 알고리즘은 STR과 AGC가 완료된 이후에 사용되어야 하지만, 위상과 주파수 옵셋에는 무관하게 작동한다. ETEO 알고리즘은 기존의 TEO 알고리즘을 확장한 알고리즘이며, MTEO 알고리즘은 ETEO 출력 특성을 개선시키고자 제안된 알고리즘이다. 또한 PREAMBLE64를 검출하기 위해 변형된 구조를 제안하였다. 모의 컴퓨터 시뮬레이션에 의해서 CDF와 최적의 임계치를 설정하였으며, 최적 임계치에 대한 P$_{M}$, P$_{F}$ 성능과 FER 성능을 모의 컴퓨터 시뮬레이션에 의해 도시하였다. 결론적으로, M=3인 MTEO 버스트 검출기가 최적의 FER 성능을 보장하는 구조로 제안되었다.

  • PDF

Advanced Railway Power Quality Detecting Algorithm Using a Combined TEO and STFT Method

  • Yoo, Je-Ho;Shin, Seung-Kwon;Park, Jong-young;Cho, Soo-Hwan
    • Journal of Electrical Engineering and Technology
    • /
    • 제10권6호
    • /
    • pp.2442-2447
    • /
    • 2015
  • Because an electric railway vehicle is a large scale moving load, it can cause various kinds of power quality problems in the railroad power system. The power quality impacts are considered as the strong instantaneous stresses to the related power systems and can cause an accelerating aging and a malfunction of the power supplying components. Therefore, it is necessary to detect the small and intermittent symptoms mixed in the voltage waveform. However, they cannot be detected by the triggering functions of the existing power analyzers installed in the railway systems. This paper will examine the drawback of some fast detection tools and propose an advanced detecting and analyzing method based on a combined TEO and STFT algorithm.

Improved thermal exchange optimization algorithm for optimal design of skeletal structures

  • Kaveh, A.;Dadras, A.;Bakhshpoori, T.
    • Smart Structures and Systems
    • /
    • 제21권3호
    • /
    • pp.263-278
    • /
    • 2018
  • Thermal Exchange Optimization (TEO) is a newly developed algorithm which mimics the thermal exchange between a solid object and its surrounding fluid. In this paper, an improved version of the TEO is developed to fix the shortcomings of the standard version. To demonstrate the viability of the new algorithm, the CEC 2016's single objective problems are considered along with the discrete size optimization of benchmark skeletal structures. Problem specific constraints are handled using a fly-back mechanism. The results show the validity of the improved TEO method compared to its standard version and a number of well-known algorithms.