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Greenhouse system is a MIMO(multi-input, multioutput), non-linear, strong coupling system. Nowadays, most of the greenhouse control methods using PID control cannot relieve the coupling between variables, so the effects of these controls are not ideal. Aiming at these problems, a feedback linearization decoupling method is designed for the coupling between CO2 concentration, temperature and humidity,...
This paper investigates nonlinear control methods for single-ended primary-inductor converters (SEPIC). The fast-switching and average models show the converter nonlinearity in terms of inductor currents, capacitor voltages, and the switching duty cycle. The control law intuitively should be nonlinear to drive and guarantee the system stability. Two different control laws based on the passivity and...
Permanent magnet synchronous motor (PMSM) is extensively used in industries. Recently, active disturbance rejection controller (ADRC) based control designs stand out due to advantages for a complex uncertain PMSM servo system. A general design procedure for the ADRC based PMSM control is discussed at the beginning. Then, the ADRC based control designs applied to PMSM servo systems are fully reviewed,...
This paper presents the design and implementation of a current controlled Rotor Flux Oriented PMSM for automotive steer-by-wire applications. The development of a realistic torque feedback reference is carried out by monitoring the steering torque while driving a commercial vehicle. The paper shall discuss the torque dynamics of the PMSM drive with respect to position demands replicating a driver...
Task outcome feedback is often used to sustain human work motivation and ensure overall productivity. Feedback can also be useful for reducing learning periods for new tasks. Two types of feedback, including knowledge of results (KR) and knowledge of performance (KP), are commonly delivered as part of motor training by using various sensory modalities (e.g., visual, auditory or kinesthetic). Unfortunately,...
Automatic essay evaluation (AEE) systems are designed to assist a teacher in the task of classroom assessment in order to alleviate the demands of manual subject evaluation. However, although numerous AEE systems are available, most of these systems do not use elaborate domain knowledge for evaluation, which limits their ability to give informative feedback to students and also their ability to constructively...
In this paper, we present an 880 MHz common-drain power amplifier (CDPA) in 130 nm CMOS technology. New PA topologies are required to address the issues of linearity, reliability, and efficiency. The CDPA is one such promising topology. Owing to the inherent feedback nature of a CDPA, the output voltage is a replica of input voltage, thus making the CDPA a highly linear amplifier with good efficiency...
In this paper, we present an 880 MHz common-drain power amplifier (CDPA) in 130 nm CMOS technology. New PA topologies are required to address the issues of linearity, reliability, and efficiency. The CDPA is one such promising topology. Owing to the inherent feedback nature of a CDPA, the output voltage is a replica of input voltage, thus making the CDPA a highly linear amplifier with good efficiency...
Finding voltage gains with Trajectance analysis is introduced in this paper. First, all paths that connect the input to output nodes of the circuit through sequential passive components and dependent active sources are determined. Second, the segment of these paths are shorted to ground and the Suspendance is calculated. Third, the contributions of each Trajectance path is multiplied by its corresponding...
This article dials with the problems of information search in company knowledge management system by keywords and belonging to some category. The approach of weight coefficients correction based on user activity statistics is considered; also, associative analysis that allows to determine keywords bonds in measure of user request is used.
In modern electronic systems, signal stability is a crucial issue. Many methods have been developed to mitigate the deviation from an ideal signal. One of them is called Automatic Gain Control, which tracks variation in an input signal to settle output amplitude. This paper proposes a Differential Automatic Gain Controller with offset stability. It is a Proportional Integral Derivative controller...
In this paper a low power, high gain self bias opamp suitable for biomedical applications has been described. A novel trans conductance boosting technique is introduced without having any additional power consumption. A simple technique of biasing the opamp has been introduced for very low offset and without having any requirement for external reference circuit. A prototype of two stage amplifier...
Numerator of the voltage gain transfer functions is directly derived with Trajectance analysis in this paper. Denominator of the voltage gain transfer functions is directly calculated by Suspendance analysis that was explained in prior publications. The voltage gain numerator is obtained by i) identifying all paths that connect the input node to output node of the circuit through sequential passive...
The number of students learning programming languages in higher education and secondary schools has substantially increased, especially in the last decade. The increasing number of (novice) programmers makes code script assessment more important. Thus, this study proposes a new marking technique based on a semi-automated assessment approach. It advocates providing detailed and consistent feedback...
Task scheduling problem has been an active area in big data framework. Arriving tasks should be assigned to suitable nodes in a big data cluster for load balancing. The system can become more efficient when the workload is well distributed among different nodes. However, the existing researches consider little about the uncertainties in the resource and service provision. Since effective processor...
For long, online learning has received criticism on not being able to provide helpful insight on students' learning, for a lack of necessary and appropriate interaction between instructor and students. Despite the fact that learning analytics (LA) are on the rise in terms of their popularity in academic institutions, the usefulness of LA come into question, especially the elements intended to provide...
In this paper we study a class of port Hamiltonian systems. Feedback transformations that preserve the structure of port Hamiltonian systems are characterized. Integrability of the corresponding Dirac structure under feedback transformation are investigated. Given two integrable port Hamiltonian systems, we study whether integrability is preserved under interconnection.
According to requirement of closed-loop combustion control and combustion process character in diesel engine, cylinder pressure is used to analyze combustion condition character, pressure difference method is introduced into combustion pressure resolution, combustion intensity and combustion phase and releasing heat are presented to describe combustion condition, the whole combustion character is...
Ocean-surface turbulent fluxes (stress and latent heat) are generated by atmospheric instability caused both by wind shear (difference between wind and current) and buoyancy (vertical density stratification). Stress depends on the vector difference between wind and current. Using the unique capability of the scatterometer in measuring stress, we demonstrated that the effect of ocean surface stress...
Conventional cooperative sensing scheme is a typical solution in cognitive radios for sensing and spectrum access under fading channel conditions and hidden node scenarios. The drawbacks of this scheme are its requirement of additional resources as well as the time delays involved in it. In this paper, we propose a mechanism for a single band structure, in which the two communicating secondary users...
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