One kind of combustible gas alarms based on industrial Ethernet was designed to prevent the gas leakage in industrial production sites, The alarm adopted the high performance microprocessor LPC2214 as the main chip. T...
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One kind of combustible gas alarms based on industrial Ethernet was designed to prevent the gas leakage in industrial production sites, The alarm adopted the high performance microprocessor LPC2214 as the main chip. The embedded operating system μC/OS-Ⅱand TCP/IP protocol stack uIP running on LPC2214 constitute a development platform of application of the combustible gas alarm, The test shows that it can automatically and continuously detect combustible gas in industrial production sites in several positions;it can give out sound-light alarm and take protective measures immediately against the gas leakage; and it can send the detected data to PC through the Ethernet interface to realize the remote detection. The designed project provides a reference to design industrial devices based on industrial Ethernet
This paper presents a novel load variation compensation algorithm in a sensor-less BLDC motor drive for a reciprocating compressor. Periodic load variation of a reciprocating compressor leads to commutation position e...
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ISBN:
(纸本)9781424424900
This paper presents a novel load variation compensation algorithm in a sensor-less BLDC motor drive for a reciprocating compressor. Periodic load variation of a reciprocating compressor leads to commutation position error and instantaneous speed variation and causes large peak currents. The major concept of this study includes tracking the pattern of load torque and controlling the motor input voltage by the commutation point and PWM depending on the tracked load torque. The suggested method can reduce the cost because this method does not require additional current sensing or voltage comparison circuit. The utility of the suggested algorithm was confirmed by simulation and experimental results of a sensor-less BLDC motor drive.
The coiling temperature control of a typical steel strip mill was investigated. Due to the high speed of a strip and complex circumstance, it is very hard to set up a cooling model with high accuracy. A simplified dyn...
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The coiling temperature control of a typical steel strip mill was investigated. Due to the high speed of a strip and complex circumstance, it is very hard to set up a cooling model with high accuracy. A simplified dynamic model was proposed, based on which a cooling control scheme with combined feedforward, feedback and adaptive algorithms was developed. Meanwhile, the genetic algorithms were used for the optimization of model parameters. Simulations with a model validated using actual plant data were conducted, and the results have confirmed the effectiveness of the proposed control methods. At last, a simulation system for coiling temperature control was developed. It can be used for new product trials and newcomer training.
Today due to the importance and necessity of implementing security systems in homes and other buildings, systems with higher certainty, lower cost and with sensor fusion methods are more attractive, as an applicable a...
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Today due to the importance and necessity of implementing security systems in homes and other buildings, systems with higher certainty, lower cost and with sensor fusion methods are more attractive, as an applicable and high performance methods for the researchers. In this paper, the application of Dempster-Shafer evidential theory and also the newer, more general one Dezert-Smarandache theory for implementing as a home security system and also using sensor data fusion have been considered. The benefits of multisensor fusion with direct connection to the control unit, in comparison with the traditional single sensor systems, have been shown.
A method for detecting spikes and slow burst in photic evoked electroencephalogram (EEG) was proposed. The spikes were detected by combining methods of the morphological filter and the similarity coefficient in the ti...
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A method for detecting spikes and slow burst in photic evoked electroencephalogram (EEG) was proposed. The spikes were detected by combining methods of the morphological filter and the similarity coefficient in the time domain. The slow burst was detected by using pole of AR model in the frequency domain. The proposed method was applied for the photic evoked EEG data containing spikes and slow burst, and brought satisfactory coincidence with the results interpreted by a qualified electroencephalographer.
Fisher discriminant analysis (FDA) is a popular method for supervised dimensionality reduction. FDA seeks for an embedding transformation such that the ratio of the between-class scatter to the within-class scatter is...
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Fisher discriminant analysis (FDA) is a popular method for supervised dimensionality reduction. FDA seeks for an embedding transformation such that the ratio of the between-class scatter to the within-class scatter is maximized. Labeled data, however, often consume much time and are expensive to obtain, as they require the efforts of human annotators. In order to cope with the problem of effectively combining unlabeled data with labeled data to find the embedding transformation, we propose a novel method, called subspace semi-supervised Fisher discriminant analysis (SSFDA), for semi-supervised dimensionality reduction. SSFDA aims to find an embedding transformation that respects the discriminant structure inferred from the labeled data and the intrinsic geometrical structure inferred from both the labeled and unlabeled data. We also show that SSFDA can be extended to nonlinear dimensionality reduction scenarios by applying the kernel trick. The experimental results on face recognition demonstrate the effectiveness of our proposed algorithm.
This study presents an apparatus for detecting Ultra Wide-Band (UWB) impulse radio (IR) signals using circuit with a normal ultra-high-speed integrated comparator, which having nonlinear dynamics characteristics with ...
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Since there are a lot of exclusive OR operations in Boolean difference algorithm, especially in solving high-order difference equation, a kind of test generation simplified method with constraint conditions is propose...
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Since there are a lot of exclusive OR operations in Boolean difference algorithm, especially in solving high-order difference equation, a kind of test generation simplified method with constraint conditions is proposed. By analyzing the Boolean difference algorithm,the result obtained was that Boolean functionchanges with variables, so Boolean difference equations can be expressed into identity. To make faults propagate to output, the constraint conditions should be put, so test patterns can be obtained only by solving the identity and constraint conditions without exclusive OR operations in this algorithm. By examples, it has been proved that simplified algorithm is correct and simple, and it is verified that test patterns can detect given faults by VB (Visual Basic) simulation.
Aimed at the problem of quickly detecting phosphorus-containing toxic gas, we used home-made hybrid PdPc-PANI as the material for sensitive film and designed a binary channel SAW sensor. We expound the basic principle...
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Aimed at the problem of quickly detecting phosphorus-containing toxic gas, we used home-made hybrid PdPc-PANI as the material for sensitive film and designed a binary channel SAW sensor. We expound the basic principle of the sensor and deduce that when using organic film as the intermediate medium of channel, different frequency output Δf was superimposed by a mathematical model using the two mechanisms of physical chemistry adsorption. According to the conditions of sound wave oscillation, we designed a signal gathering circuit whose oscillation frequency is 146 ± 5 MHz. Using lithium tantalate as piezoelectric substrate, through MEMS micro-fabrication we made finger-cross electrodes couple and hot film. We adopted vacuum deposition technology to make material of sensitive film into film, which modified the center of the SAW channel to compose the SAW sensor. The testing result indicates that when material has the best sensitivity, the mixture ratio is PdPc0.35PANI0.65. When the chip is heated to 60-80C, it can increase the performance, the responsive time is less than or equal to 30 s;The gas concentration of output and testing is consistent with that in the mathematic model, and is the N-style linear relation of linear change rate -110 kHz (mg/m3). The SAW sensor counteracts the interference of gasoline oil and carbon dioxide and so on;Through the checking of stability for 80 days, Δf is less than or equal to +0.1 kHz, which meets the requirement for practical use.
This paper presents a new clustering algorithm to solve the blind identification problem of digital communication signal modulation types. the algorithm utilized the instantaneous frequency and instantaneous phase of ...
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