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1.
In this paper, the presence of source stack and heterogeneous gate dielectric material in the structure of an n-channel tunnel FET (TFET) is investigated. 相似文献
2.
Solving the Problem of Forbidden States in Discrete Event Systems: A Novel Systematic Method for Reducing the Number of Control Places 下载免费PDF全文
Meysam Zareiee Abbas Dideban Ali A. Orouji Hadi Soltanizadeh 《Asian journal of control》2015,17(3):1006-1015
This paper deals with the problem of forbidden states in Discrete Event Systems modelled by non‐safe Petri Nets. To avoid these states, some Generalized Mutual Exclusion Constraints can be assigned to them. These constraints limit the weight sum of tokens in some places and can be enforced on the system using control places. When the number of these constraints is large, a large number of control places should be added to the system. In this paper, a method is presented to assign the small number of constraints to forbidden states using some states which cover the forbidden states. So, a small number of control places are added to the system leading to obtaining a maximally permissive controller. 相似文献
3.
This paper deals with the problem of forbidden states in safe Petri nets to obtain a maximally permissive controller. To prevent the system from entering the forbidden states, assigning some constraints to them is possible. The constraints can be enforced on the system using control places. When the number of forbidden states is large, a large number of constraints should be assigned to them. This results in a large number of control places being added to the model of the system, which causes a complicated model. Some methods have been proposed to reduce the number of constraints. Nevertheless, they do not always give the best results. In this paper, two ideas are offered to reduce the number of constraints, giving a more simplified controller. 相似文献
4.
Hamid Reza Shokouhfar Hamed Jooypa Daryoosh Dideban 《Analog Integrated Circuits and Signal Processing》2018,95(2):295-306
In this paper, the context of modeling of the impact of mismatch and statistical variations on analogue circuit building blocks is emphasized. The aim is to develop a new algorithm which predicts the statistical behavior of important parameters of an amplifier including output resistance, voltage gain and trans-conductance. The relative error of standard deviation of statistical parameters will remain less than 5% compared with the most accurate Monte-Carlo (MC) simulations using atomistic library model-cards. In comparison with other models which are based on the normal distribution of parameters, the proposed model does not need this limiting presumption. On the other hand, the proposed algorithm is more efficient compared with time consuming MC atomistic simulations. 相似文献
5.
This paper deals with the problem of forbidden states in discrete event systems based on Petri net models. So, a method is presented to prevent the system from entering these states by constructing a small number of generalized mutual exclusion constraints. This goal is achieved by solving three types of Integer Linear Programming problems. The problems are designed to verify the constraints that some of them are related to verifying authorized states and the others are related to avoiding forbidden states. The obtained constraints can be enforced on the system using a small number of control places. Moreover, the number of arcs related to these places is small, and the controller after connecting them is maximally permissive. 相似文献
6.
In this paper, we present an efficient method based on safe Petri Nets to construct a controller. A set of linear constraints allows forbidding the reachability of specific states. The number of these so-called forbidden states, and consequently the number of constraints, are large and lead to a large number of control places. A systematic method to reduce the size and the number of constraints for safe Petri Nets is offered. By using a method based on Petri Net invariants, maximal permissive controllers are determined. 相似文献
7.
Preventing systems from entering to forbidden states is a crucial issue in discrete event systems control. Adding supervisors to the system is a common method to avoid entering to forbidden states. In discrete event systems modeled by Petri net adding a supervisor could be done by means of control places. Since, the time is not considered in designing this supervisor, in presence of uncontrollable transitions adding control places can lead to increase the operation time of the system modeled by timed Petri net. Because, the firing of some transitions is prevented when it is not necessary. So, to design a more efficient controller, we will be required to use time information of the system component. Therefore, in this paper, a method for optimizing the time behavior of a supervised timed Petri net will be proposed. To obtain an efficient operation, some timed places as timer will be added to the net. The time of this timer places is calculated to permit firing of some controllable transitions in order to enter into some weakly forbidden states while entering to forbidden states is prevented. This concept leads to increase the speed of system as well as obtain an acceptable operation. This method can be applied for all systems modeled by Petri nets. The efficiency of proposed approach will be discussed and validated with a case study. 相似文献
8.
Silicon - In this Research, the Effect of Source Stack Engineering on the Drive Current of a Proposed Silicon on Insulator-Tunnel FET (SOI-TFET) Is Investigated. The Proposed TFET Scheme Is Similar... 相似文献
9.
Ali Dideban Hamidreza Habibiyan Hassan Ghafoorifard 《Photonic Network Communications》2017,34(3):468-477
This paper presents a novel photonic crystal-based channel drop filter in a silicon-on-insulator platform. The proposed structure consists of two line-defect waveguides and a special circular cavity between them. The effects of structural parameters and fabrication errors on resonant wavelength and drop efficiency of output signal are analyzed. Band structure calculations and propagation of electromagnetic field through device are done by plane wave expansion and finite-difference time-domain methods, respectively. In our design, drop efficiency of more than 81% and quality factor of about 2246 are achievable. Simulation results show the effectiveness of the proposed filter for narrowband applications in photonic communication systems. 相似文献
10.
We investigate theoretically the possibility of exploiting the electrically tunable band gap property of silicene to achieve field effect transistor with improved characteristics. We find that the silicene field effect transistor where a band gap is introduced through a perpendicular electric field shows a subthreshold swing smaller than 60 mV/decade and a switching effect with high on/off current ratio exceeding \(10^{5}\). We find also that the device output characteristic displays a very good saturation due to improved pinch-off of the channel, stemming from the electrically induced band gap. 相似文献