• 제목/요약/키워드: Flow Detection

검색결과 1,247건 처리시간 0.032초

HPLC에 의한 가시오가피 및 오가피 중 Hyperin의 정량 (Determination of Hyperin in Acanthopanax senticosus and A. sessiliflorus by HPLC)

  • 이상현;정하숙;신국현;김박광
    • 약학회지
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    • 제48권4호
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    • pp.231-235
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    • 2004
  • A new high performance liquid chromatographic method was applied for the determination of hyperin in Acanthopanax senticosus and A sessiliflorus. The stationary phase used was $\beta$-Bondapak $C_{18}$ reverse-phase column and a mobile phase program was a gradient of acetonitrile and distilled water at a flow rate of 1.0 ml/min. Hyperin was detected at 210 nm, and the analysis was successfully carried out within 20 min. Hyperin was detected in the one year-grown and two years-grown stem of A senticosus (0.47 and 0.13 mg/g, respectively) and A sessiliflorus (0.14 and 0.03 mg/g, respectively). Hyperin was detected in the main and branch root of A sessiliflorus (0.30 and 0.09 mg/g, respectively). But there is no detection of hyperin in the main and branch root of A senticosus.

The Composition Dependence Selectivity Changes by Plasticizer at the Cation Sensors Based on Tetracycline Antibiotics

  • Baek, Jong-Gyu;Kim, Jin-San;Paeng, Insook Rhee;Paeng, Ki-Jung
    • Bulletin of the Korean Chemical Society
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    • 제29권1호
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    • pp.165-167
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    • 2008
  • The performances of tetracycline based cation selective polymeric membrane electrodes of many sets with different plasticizers were investigated as the selectivity of ion-selective electrodes and optodes are greatly influenced by membrane solvent and also controlled by plasticizers. The membrane 1 with Bis(2-ethylhexyl) sebacate (DOS) and additive shows good potentiometric performance toward Ca2+ (slope: 27.8 mV per decade; DL: -4.52) including selectivity. Contrastingly, membrane 4 with Dibutyl phthalate (DBP) shows near-Nernstian response, it has also shown the best measuring range and detection limit for Ca2+ (29.5 mV and -5.10) and Mg2+ (24.4 mV and -5.04) and the least selectivity has been also observed between Ca2+ and Mg2+. When the membrane 1 and 4 were used together to flow system, we could determine the concentration of Ca2+ and Mg2+, simultaneously.

공압서보시스템에 의한 미세 간극제어 시스템 설계 (Fine Gap Control Using Pneumatic Servo System)

  • 김동환;김영진;정대화
    • 한국정밀공학회지
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    • 제19권12호
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    • pp.45-56
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    • 2002
  • A pneumatic servo system requiring a fine gap control in a photo-electric sensor which is used for a LCD array detection device is introduced. The gap controlled by the pneumatic servo system remains within around 50~80 ${\mu}{\textrm}{m}$, and the system possesses an effect to eliminate undesirable particles on the LCD plate by blowing air out. The air flow rate is initially controlled by a servo valve and expanded by a booster valve, thus the controlled air pressure contributes to maintaining an appropriate gap between the LCD plate and photo-electric sensor An air floating plate of two degrees of freedom is designed and fabricated, and a fine tilting motion control is also implemented by assigning different gap commands. The pressure control and direct gap control are proposed, and each performance is verified experimentally.

A Study on Ceiling Light and Guided Line based Moving Detection Estimation Algorithm using Multi-Camera in Factory

  • Kim, Ki Rhyoung;Lee, Kang Hun;Cho, Su Hyung
    • International Journal of Internet, Broadcasting and Communication
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    • 제10권4호
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    • pp.70-74
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    • 2018
  • In order to ensure the flow of goods available and more flexible, reduce labor costs, many factories and industrial zones around the world are gradually moving to use automated solutions. One of them is to use Automated guided vehicles (AGV). Currently, there are a line tracing method as an AGV operating method, and a method of estimating the current position of the AGV and matching with a factory map and knowing the moving direction of the AGV. In this paper, we propose ceiling Light and guided line based moving direction estimation algorithm using multi-camera on the AGV in smart factory that can operate stable AGV by compensating the disadvantages of existing AGV operation method. The proposed algorithm is able to estimate its position and direction using a general - purpose camera instead of a sensor. Based on this, it can correct its movement error and estimate its own movement path.

다중경로 페이딩 전송로에서 직접시퀀스 확산대역 다원접속 시스템의 포착성능 (Acquisition performance of a direct-sequence spread-specturm multiple-access system in a multipath fading channel)

  • 김진영;이재홍
    • 한국통신학회논문지
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    • 제21권5호
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    • pp.1230-1239
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    • 1996
  • This paper analyzes matched-filter acquistion performance of a direct-sequence spread-specturm multiple-access system in a Rayleigh fading channel. For an application of multiple access system, multiple access interference is considered in the performance analysis. A signal flow graph technique is used to derive mean acquisition time in terms of detection and false alarm probabilities. As aresult of performance analysis, it is shown that mean acquisition time increases as fading rate becomes faster andthe numbre of users increases, and it decreases as a matched-filter length becomes logner. The variation of parameter values hs much influence on acquisition performance as SNR/chip becomes smaller.

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아음속 풍동을 이용한 구조물 형상 변화에 따른 살리실산메틸 확산 유동 연구 (A Study on the Methyl Salicylate Dispersion in the Vicinity of Obstacles by Wind Tunnel Test)

  • 홍창기;엄환섭;최승기;김윤제
    • 한국유체기계학회 논문집
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    • 제17권6호
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    • pp.69-73
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    • 2014
  • To predict flow fields and chemical agent dispersion in urban area, wind tunnel experiments was performed. The agent was adopted MS (methyl salicylate) because the real chemical agent is unsafe. The exact concentration of methyl salicylate was generated by the commercial gas generator (STI-2500) and three different obstacle shapes were applied (i.e., rectangular, cylinder and pyramid). The concentration was measured with the qualified ion mobility sensor and gas chromatography. The data necessary for virtual test method of the real chemical agent were obtained.

A Study on the Automatic Diagnosis of ECG

  • Jeong, Gu-Young;Yu, Kee-Ho;Kwon, Tae-Kyu;Lee, Seong-Cheol
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.55.4-55
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    • 2001
  • Analyzing the ECG signal, we can find heart disease. Myocardial ischemia is a disorder of cardiac function caused by insufficient blood flow to the muscle tissue of the heart. Myocardial ischemia is inscribed on ST-segment of the ECG during and after patient takes exercise or is under stress, but after long time past, the ECG pattern is return to steady state. Therefore, it is necessary to monitor and analyze the ECG signal continuously for patient or aged people. Our primary purpose is the detection of temporary change of the ST-segment of ECG automatically. In the signal processing, the wavelet transform decomposes the ECG signal into high and low frequency components using wavelet function. Recomposing the high frequency bands including QRS complex, we can detect QRS complex more easily ...

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가스터빈 블레이드 끝단 형상에 따른 블레이드 끝단 및 그 주변에서의 열전달 계수 변화 (Effect of Blade Tip Geometry on Heat Transfer Coefficients on Gas Turbine Blade Tips and Near Tip Regions)

  • 곽재수
    • 대한기계학회논문집B
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    • 제30권4호
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    • pp.328-336
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    • 2006
  • Detailed heat transfer coefficient distributions an two. types of gas turbine blade tip, plane tip and squealer tip, were measured using a hue-detection base transient liquid crystals technique.. The heat transfer coefficients an the shroud and near tip regions of the pressure and suction sides af the blade were also. measured. The heat transfer measurements were taken at the three different tip gap clearances af 1.0%, 1.5%, and 2.5% of blade span. Results shaw the overall heat transfer coefficients on the tip and shroud with squealer tip blade were lower than those with plane tip blade. By using squealer tip, however, the reductions af heat transfer coefficients near the tip regions of the pressure and suction sides were nat remarkable.

심근관류 PET (Myocardial Perfusion PET)

  • 조인호;공은정
    • Nuclear Medicine and Molecular Imaging
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    • 제43권3호
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    • pp.207-214
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    • 2009
  • Positron emission tomogrpahy (PET) represents the most advanced scintigraphic imaging technology. With the increase in availability of PET, the clinical use of PET has grown in medical fields. This can be employed for cardiovascular research as well as for clinical applications in patients with various cardiovascular disease. PET allows non-invasive functional assessment of myocardial perfusion, substrate metabolism and cardiac innervation and receptors as well as gene expression in vivo. PET is regarded as the gold standard for the detection of myocardial viability, and it is the only method available for the quantitative assessment of myocardial blood flow. This review focuses on the clinical applications of myocardial perfusion PET in coronary artery disease.

Directing the turning behavior of carp using virtual stimulation

  • Kim, Cheol-Hu;Kim, Dae-Gun;Kim, Daesoo;Lee, Phill-Seung
    • Ocean Systems Engineering
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    • 제7권1호
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    • pp.39-51
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    • 2017
  • Fishes detect various sensory stimuli, which may be used to direct their behavior. Especially, the visual and water flow detection information are critical for locating prey, predators, and school formation. In this study, we examined the specific role of these two different type of stimulation (vision and vibration) during the obstacle avoidance behavior of carp, Cyprinus carpio. When a visual obstacle was presented, the carp efficiently turned and swam away in the opposite direction. In contrast, vibration stimulation of the left or right side with a vibrator did not induce strong turning behavior. The vibrator only regulated the direction of turning when presented in combination with the visual obstacle. Our results provide first evidence on the innate capacity that dynamically coordinates visual and vibration signals in fish and give insights on the novel modulation method of fish behavior without training.