scholarly journals Analysis and Design of Network-Based Control Systems with Binary Modulation

2014 ◽  
Vol 2014 ◽  
pp. 1-7
Author(s):  
Shunli Zhao ◽  
Xunhe Yin ◽  
Xueye Wei
Keyword(s):  
Control Systems ◽  
Signal To Noise Ratio ◽  
Channel Noise ◽  
Linear Matrix ◽  
Computer Communication ◽  
Analysis And Design ◽  
The Past ◽  
Binary Modulation ◽  
Shift Keying ◽  
The Stability

Network-based control systems have been emerging technologies in control and computer communication fields over the past decade. This paper focuses on the analysis and design of network-based control systems with binary modulation. First, it is shown that different modulations can result in different delays which are inevitable in network-based control systems. The delay can be seen as constant delay when the transmission time is the main consideration. Second, channel noise can result in bit error while bit error is seen as active packet loss in this paper, in this context, the conditions of signal-to-noise ratio (SNR) for binary modulation that can guarantee the stability of systems are obtained according to the proposed algorithm. Third, the system with delay and noisy communication can be modeled as an asynchronous dynamic system (ADS); in addition, the stability is analyzed and controller is designed in terms of Lyapunov function and linear matrix inequality (LMI) scheme. Finally, without loss of generality, numerical simulation demonstrates the effectiveness of the proposed scheme and designed controller based on binary amplitude shift keying (2ASK) modulation.

scholarly journals Experimental Study of the Chaotic Jerk Circuit Application for Chaos Shift Keying

2021 ◽  
Vol 58 (4) ◽  
pp. 55-68
Author(s):  
F. Capligins ◽  
A. Litvinenko ◽  
A. Aboltins ◽  
E. Austrums ◽  
A. Rusins ◽  
...  
Keyword(s):  
Experimental Study ◽  
Voltage Drop ◽  
Experimental Studies ◽  
Chaotic Synchronization ◽  
Channel Noise ◽  
Error Feedback ◽  
Shift Keying ◽  
The Stability ◽  
Chaos Shift Keying ◽  
The Impact

Abstract The paper presents a study of the chaotic jerk circuit (CJC) employment capabilities for digital communications. The concept of coherent chaos shift keying (CSK) communication system with controlled error feedback chaotic synchronization is proposed for a specific CJC in two modifications. The stability of chaotic synchronization between the two CJCs was evaluated in terms of voltage drop at the input of the slave circuit and the impact of channel noise using simulations and experimental studies.

scholarly journals Fault Detection for Wireless Network Control Systems with Stochastic Uncertainties and Time Delays

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Jie Zhang ◽  
Pengfei Guo ◽  
Ming Lyu ◽  
Hamid Reza Karimi ◽  
Yuming Bo
Keyword(s):  
Fault Detection ◽  
Control Systems ◽  
Wireless Network ◽  
Time Delays ◽  
Sufficient Conditions ◽  
Network Control ◽  
Linear Matrix ◽  
Network Control Systems ◽  
The Stability ◽  
Stochastic Uncertainties

The fault detection problem is investigated for a class of wireless network control systems which has stochastic uncertainties in the state-space matrices, combined with time delays and nonlinear disturbance. First, the system error observer is proposed. Then, by constructing proper Lyapunov-Krasovskii functional, we acquire sufficient conditions to guarantee the stability of the fault detection observer for the discrete system, and observer gain is also derived by solving linear matrix inequalities. Finally, a simulation example shows that when a fault happens, the observer residual rises rapidly and fault can be quickly detected, which demonstrates the effectiveness of the proposed method.

A High Performance Fourth-Order Single-Loop Sigma Delta Modulator Applied in Micro-Inertial Sensors

2012 ◽  
Vol 503 ◽  
pp. 303-307
Author(s):  
Peng Fei Wang ◽  
Yuan Yuan ◽  
Dong Bo Wang ◽  
Xiao Wei Liu ◽  
Jun'an Liu
Keyword(s):  
Fourth Order ◽  
High Performance ◽  
Inertial Sensors ◽  
Signal To Noise Ratio ◽  
System Level ◽  
Sigma Delta Modulator ◽  
Sigma Delta ◽  
Analysis And Design ◽  
The Stability ◽  
Σδ Modulator

This paper presents a fourth-order sigma delta (ΣΔ)modulator applied in micro-inertial sensors. After a introduction of sigma-delta modulator and its application in micro-inertial sensors, the system-level analysis and design is given and the gain coefficients is calculated. By the use of root locus, the stability of high order ΣΔ modulator is analyzed and it is got the minimum value of quantizer gain k is 0.287. The simulation shows that the signal to noise ratio (SNR) is 121.6 dB and the effective number of bits (ENOB) is 19.91 bits. When input level is smaller than -6 dBFs, the quantizer and integrators would not be overload and work well.

Improved over-approximation method for modelling and stability analysis of networked control systems

2016 ◽  
Vol 39 (2) ◽  
pp. 131-140 ◽  
Author(s):  
Milad Farsi ◽  
Reza Mahboobi Esfanjani
Keyword(s):  
Control Systems ◽  
Approximation Scheme ◽  
Linear Models ◽  
Networked Control Systems ◽  
Networked Control ◽  
Superior Performance ◽  
Linear Matrix ◽  
Matrix Inequalities ◽  
Challenging Problem ◽  
Analysis And Design

Networked control systems (NCSs) are commonly modelled by the switched systems involving exponential non-linearities. A challenging problem is to obtain a tight linear approximation of the mentioned non-linear models to derive analysis and design criteria in terms of linear matrix inequalities (LMIs), which can be easily handled using the well-established algorithms. The present paper introduces a novel procedure to achieve an improved polytopic over-approximation of the non-linearities emerged in the modelling of NCSs. Moreover, stability of the NCSs is analysed to verify the merits of the proposed method; to this end, a benchmark numerical example is presented to illustrate the superior performance of the suggested approximation scheme compared with the existing approaches in the literature.

scholarly journals Design of Software-Defined Radio-Based Adaptable Packet Communication System for Small Satellites

Aerospace ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 159
Author(s):  
Yasir M. O. ABBAS ◽  
Kenichi Asami
Keyword(s):  
Software Defined Radio ◽  
Communication Systems ◽  
Signal To Noise Ratio ◽  
Data Rate ◽  
Channel Noise ◽  
Modulation Scheme ◽  
Small Satellites ◽  
Feedback Message ◽  
Data Rates ◽  
Shift Keying

Software-defined radio (SDR) devices have made a massive contribution to communication systems by reducing the cost and development time for radio frequency (RF) designs. SDRs opened the gate to programmers and enabled them to increase the capabilities of these easily manipulated systems. The next step is to upgrade the reconfigurability into adaptability, which is the focus of this paper. This research contributes to improving SDR-based systems by designing an adaptable packet communication transmitter and receiver that can utilize the communication window of CubeSats and small satellites. According to the feedback from the receiver, the transmitter modifies the characteristics of the signal. Theoretically, the system can adopt many modes, but for simplicity and to prove the concept, here, the changes are limited to three data rates of the Gaussian minimum shift keying (GMSK) modulation scheme, i.e., 2400 bps GMSK, 4800 bps GMSK and 9600 bps GMSK, which are the most popular in amateur small satellites. The system program was developed using GNU Radio Companion (GRC) software and Python scripts. With the help of GRC software, the design was simulated and its behavior in simulated conditions observed. The transmitter packetizes the data into AX.25 packets and transmits them in patches. Between these patches, it sends signaling packets. The patch size is preselected. Alternatively, the receiver extracts the data and saves it in a dedicated file. It directly replies with a feedback message whenever it gets the signaling packets. Based on the content of the feedback message, the characteristics of the transmitted signal are altered. The packet rate and the actual useful data rate are measured and compared with the selected data rate, and the packet success rate of the system operating at a fixed data rate is also measured while simulating channel noise to achieve the desired Signal-to-Noise Ratio (SNR).

ANALISIS KESTABILAN LERENG DINDING AKHIR DI PIT BARATLAUT PADA PENAMBANGAN BATUBARA DI PT. PUTERA BARA MITRA , KECAMATAN MENTEWE, KALIMANTAN SELATAN

KURVATEK ◽  
2018 ◽  
Vol 3 (1) ◽  
pp. 21-34
Author(s):  
Untung Wahyudi ◽  
Excelsior T P ◽  
Luthfi Wahyudi
Keyword(s):  
Slope Stability ◽  
Mining Operation ◽  
Subsurface Water ◽  
Mining System ◽  
Mine Site ◽  
Analysis And Design ◽  
The Stability ◽  
End Wall ◽  
Wall Slope ◽  
Mining Slope

PT. Putera Bara Mitra used open mining system for mining operation, Yet the completion of study on the end wall slope stability that  undertaken by geotechnical PT. Putera Bara Mitra in Northwest Pit and the occured a failure in the low wall on the 1st June 2012 led to the need for analysis and design the overall slope at the mine site. To analyze and design the overall slope, used value of the recommended minimum safety. The value was based on company for single slope SF ≥ 1.2 and SF ≥ 1.3 for overall slope. The calculation used Bichop method with the help of software slide v 5.0. Geometry improvements was done at the low slopes that originally single wall with a 30 m bench height and a slope 70° with SF = 0.781, into 4 levels with SF = 1.305. The analysis explained the factors that affect the stability of the low wall included the mining slope geometry, unfavorable drainase system, material stockpiles and seismicity factors. It was necessary to do prevention efforts to maintain the stability of the slope included the redesign to slope geometry, handling surface and subsurface water in a way to control slopes draining groundwater, vegetation stabilization using and monitoring slope using Total Station with Prism and Crackmeter to determine the movement of cracks visible on the surface. 

TO THE STABILITY OF TANK VEHICLES IN THE BRAKE MODE

2019 ◽  
pp. 27-32
Author(s):  
Denys Popelysh ◽  
Yurii Seluk ◽  
Sergyi Tomchuk
Keyword(s):  
Mathematical Model ◽  
Control Systems ◽  
Distribution Systems ◽  
Traffic Accidents ◽  
Road Traffic ◽  
Center Of Mass ◽  
Dynamic Processes ◽  
Course Stability ◽  
The Stability ◽  
Tank Vehicles

This article discusses the question of the possibility of improving the roll stability of partially filled tank vehicles while braking. We consider the dangers associated with partially filled tank vehicles. We give examples of the severe consequences of road traffic accidents that have occurred with tank vehicles carrying dangerous goods. We conducted an analysis of the dynamic processes of fluid flow in the tank and their influence on the basic parameters of the stability of vehicle. When transporting a partially filled tank due to the comparability of the mass of the empty tank with the mass of the fluid being transported, the dynamic qualities of the vehicle change so that they differ significantly from the dynamic characteristics of other vehicles. Due to large displacements of the center of mass of cargo in the tank there are additional loads that act vehicle and significantly reduce the course stability and the drivability. We consider the dynamics of liquid sloshing in moving containers, and give examples of building a mechanical model of an oscillating fluid in a tank and a mathematical model of a vehicle with a tank. We also considered the method of improving the vehicle’s stability, which is based on the prediction of the moment of action and the nature of the dynamic processes of liquid cargo and the implementation of preventive actions by executive mechanisms. Modern automated control systems (anti-lock brake system, anti-slip control systems, stabilization systems, braking forces distribution systems, floor level systems, etc.) use a certain list of elements for collecting necessary parameters and actuators for their work. This gives the ability to influence the course stability properties without interfering with the design of the vehicle only by making changes to the software of these systems. Keywords: tank vehicle, roll stability, mathematical model, vehicle control systems.

Stability and Folding of the Unusually Stable Hemoglobin from Synechocystis is Subtly Optimized and Dependent on the Key Heme Pocket Residues.

2020 ◽  
Vol 27 ◽  
Author(s):  
Sheetal Uppal ◽  
Mohd. Asim Khan ◽  
Suman Kundu
Keyword(s):  
Molten Globule ◽  
Life Forms ◽  
Model System ◽  
Heme Pocket ◽  
The Past ◽  
Specific Manner ◽  
Delivery Vehicles ◽  
The Stability ◽  
Key Residues ◽  
Synechocystis Sp

Aims: The aim of our study is to understand the biophysical traits that govern the stability and folding of Synechocystis hemoglobin, a unique cyanobacterial globin that displays unusual traits not observed in any of the other globins discovered so far. Background: For the past few decades, classical hemoglobins such as vertebrate hemoglobin and myoglobin have been extensively studied to unravel the stability and folding mechanisms of hemoglobins. However, the expanding wealth of hemoglobins identified in all life forms with novel properties, like heme coordination chemistry and globin fold, have added complexity and challenges to the understanding of hemoglobin stability, which has not been adequately addressed. Here, we explored the unique truncated and hexacoordinate hemoglobin from the freshwater cyanobacterium Synechocystis sp. PCC 6803 known as “Synechocystis hemoglobin (SynHb)”. The “three histidines” linkages to heme are novel to this cyanobacterial hemoglobin. Objective: Mutational studies were employed to decipher the residues within the heme pocket that dictate the stability and folding of SynHb. Methods: Site-directed mutants of SynHb were generated and analyzed using a repertoire of spectroscopic and calorimetric tools. Result: The results revealed that the heme was stably associated to the protein under all denaturing conditions with His117 playing the anchoring role. The studies also highlighted the possibility of existence of a “molten globule” like intermediate at acidic pH in this exceptionally thermostable globin. His117 and other key residues in the heme pocket play an indispensable role in imparting significant polypeptide stability. Conclusion: Synechocystis hemoglobin presents an important model system for investigations of protein folding and stability in general. The heme pocket residues influenced the folding and stability of SynHb in a very subtle and specific manner and may have been optimized to make this Hb the most stable known as of date. Other: The knowledge gained hereby about the influence of heme pocket amino acid side chains on stability and expression is currently being utilized to improve the stability of recombinant human Hbs for efficient use as oxygen delivery vehicles.

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