A capacitive immunosensor measurement system with a lock-in amplifier and potentiostatic control by software

Except for system noise, the sunlight interference can severely influence the result of fluorescence in situ measurement. In this paper, we analyzed the noise sources of the fluorescence in situ measurement system, discussed the characteristics of sunlight interference, and studied the performances of three sunlight interference suppression methods that respectively based on pulse width modulation, lock-in amplifier and pseudorandom sequence modulation. Experiment results show that methods based on lock-in amplifier and pseudorandom sequence modulation can effectively suppress sunlight interference.

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Wideband magnetoelectric measurement system with the application of a virtual multi-channel lock-in amplifier

Measurement Science and Technology ◽

10.1088/0957-0233/19/4/045702 ◽

2008 ◽

Vol 19 (4) ◽

pp. 045702 ◽

Cited By ~ 28

Author(s):

Jun Lu ◽

De-An Pan ◽

Bai Yang ◽

Lijie Qiao

Keyword(s):

Measurement System ◽

Lock In

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Development of 3-D electromagnetic field intensity measurement system using infrared 2-D lock-in amplifier

2008 International Symposium on Electrical Insulating Materials (ISEIM 2008) ◽

10.1109/iseim.2008.4664504 ◽

2008 ◽

Author(s):

N. Chiyo ◽

Y. Tanaka ◽

A. Nishikata ◽

T. Maeno

Keyword(s):

Electromagnetic Field ◽

Field Intensity ◽

Measurement System ◽

Intensity Measurement ◽

Lock In

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Experimental study on vapour pressure of dimethyl ether blended in diesel oil

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/09544070jauto477 ◽

2007 ◽

Vol 221 (7) ◽

pp. 889-892 ◽

Cited By ~ 5

Author(s):

Genbao Li ◽

Longbao Zhou ◽

Shenghua Liu ◽

Keyu Pan

Keyword(s):

Experimental Study ◽

Dimethyl Ether ◽

Measurement System ◽

Vapour Pressure ◽

Room Temperature ◽

Diesel Oil ◽

High Accuracy ◽

Supply System ◽

Property Measurement ◽

Lock In

Experiments have been conducted to determine the vapour pressure of dimethyl ether (DME) blended in diesel oil in a thermophysical property measurement system with high accuracy. Based on previous research on the viscosity of DME blends, three blends at 10, 20, and 30 wt% DME in diesel oil were chosen for this study. Experimental results indicate that DME can be soluble in diesel oil at room temperature. The vapour pressure of blends is lower than that of pure DME at a certain temperature and decreases with increase in diesel oil in DME, which helps to eliminate vapour lock in the fuel supply system of the engines. In addition, the cloud point of blends decreases as the fraction of DME in the diesel oil increases, which is beneficial to the operation of the engines at a lower ambient temperature.

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Methods for Detection of Bioimpedance Variations in Resource Constrained Environments

Sensors ◽

10.3390/s20051363 ◽

2020 ◽

Vol 20 (5) ◽

pp. 1363

Author(s):

Eiko Priidel ◽

Paul Annus ◽

Andrei Krivošei ◽

Marek Rist ◽

Raul Land ◽

...

Keyword(s):

Measurement System ◽

Dynamic Range ◽

Current Paper ◽

Variable Component ◽

Noise Levels ◽

Static Component ◽

Wideband Noise ◽

Constrained Environments ◽

Electrical Bioimpedance ◽

Lock In

Changes in a certain parameter are often a few magnitudes smaller than the base value of the parameter, specifying significant requirements for the dynamic range and noise levels of the measurement system. In case of electrical bioimpedance acquisition, the variations can be 1000 times smaller than the entire measured value. Synchronous or lock-in measurement of these variations is discussed in the current paper, and novel measurement solutions are presented. Proposed methods are simple and robust when compared to other applicable solutions. A common feature shared by all members of the group of the proposed solutions is differentiation. It is achieved by calculating the differences between synchronously acquired consecutive samples, with lock-in integration and analog differentiation. All these methods enable inherent separation of variations from the static component of the signal. The variable component of the bioimpedance can, thus, be acquired using the full available dynamic range of the apparatus for its detection. Additive disturbing signals and omnipresent wideband noise are considered and the method for their reduction is proposed.

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A Linear Least Square with Duffing Chaotic Detection Designed in Micro-Distance Movement Measurement System

Journal of Advanced Computational Intelligence and Intelligent Informatics ◽

10.20965/jaciii.2016.p0287 ◽

2016 ◽

Vol 20 (2) ◽

pp. 287-293

Author(s):

Xiao Lin ◽

◽

Yaping Dai ◽

Linhui Zhao ◽

Keyword(s):

High Precision ◽

Relative Error ◽

Measurement System ◽

Displacement Measurement ◽

Least Square ◽

Strain Gauges ◽

Measurement Framework ◽

Simulation Results ◽

Lock In ◽

Linear Least Square

High precision micro displacement measurement framework is fundamental for drilling strain gauges. We replaced the traditional lock-in amplifier method by the linear least square (LLS) based on Duffing chaotic detection (DCD) in drilling strain gauges. Simulation results showed that LLS based on DCD has a relative error 7.7% when SNR = −20.79 dB. It is 410.1% lower than lock-in amplifier method in the detection. Even more, the design and realization of LLS based on DCD is easier than lock-in amplifier method.

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