scholarly journals A Criterion for Determining the Optimal Position of the Demodulate-and-Forward (DMF) Relay

2021 ◽  
Vol 8 (6) ◽  
pp. 847-853
Author(s):  
Faton Maliqi ◽  
Bleron Klaiqi
Keyword(s):  
Theoretical Analysis ◽  
Simulation Analysis ◽  
Optimal Position ◽  
Trade Off ◽  
Transmission Path ◽  
Simple Nature

This paper considers the issue of selecting the optimal position where a Relay could be fixed to enable the communication between a Source and a Destination. Our analysis is focused on the case when Relay works on Demodulate-and-Forward (DMF) mode, due its simple nature in implementation. DMF Relay only demodulates the received signals from the Source without checking the integrity of the signals and it may happen that it forwards the erroneous signals toward the Destination. Since moving the Relay in different positions between the Source and the Destination brings different performances, we are interested to find the position at which the benefit of using the Relay is maximized. To help us find this optimal position analytically and numerically, we have introduced a criterion which relies on the trade-off between the demodulation errors on the channel S-R and the ability of the Relay to succeed on the transmission path R-D, where the theoretical analysis of the criterion matches perfectly with the simulation analysis. Moreover, in a scenario of having more than one Relay, this criterion helps us to choose the best instantaneous Relay for cooperation. The comparison of our proposed criterion with a referent criterion from the literature, has shown that our criterion outperforms the referent criterion.

A Simulation Analysis on the Tradeoff Between Cost and Risk in Replicating ELS (Equity-Linked Securities) with Transactions Costs: The Early Redeemable Case

2009 ◽  
Vol 17 (2) ◽  
pp. 1-47
Author(s):  
Jun Young Park ◽  
Chongseok Hyun
Keyword(s):  
Transaction Costs ◽  
Simulation Analysis ◽  
Transactions Costs ◽  
Proportional Transaction Costs ◽  
Underlying Asset ◽  
Trade Off ◽  
Computational Burden ◽  
Considerable Impact ◽  
The Right ◽  
Mean Variance

The trade-off between cost and risk of discretely rebalanced ELS hedges is analyzed under the proportional transaction costs. The analysis shows that the transaction costs have a considerable impact on the hedging performance. The trade-off, or mean-variance graphs move in the right and lower directions in cases that the drift or the volatility of the underlying asset increases, the redemption level of the ELS decreases, or the maturity of the ELS gets longer. The underlying asset move-based strategy (UAMB) reveals better performances than the time-based strategy (TS), while the delta move-based strategy (DMB) shows worse results. However, as the volatility of the underlying asset grows, the time-based strategy shows worse performances than the other two strategies does. The difficulty of computational burden in simulating the hedge procedure is alleviated using the vectorized scheme, which makes the simulation analysis in feasible time.

Role of Trench Bottom Shielding Region on Switching Characteristics of 4H-SiC Double-Trench Mosfets

2018 ◽  
Vol 924 ◽  
pp. 748-751 ◽  
Author(s):  
Shinya Kyogoku ◽  
Katsuhisa Tanaka ◽  
Keiko Ariyoshi ◽  
Ryosuke Iijima ◽  
Yusuke Kobayashi ◽  
...  
Keyword(s):  
Dynamic Characteristics ◽  
Simulation Analysis ◽  
Static Characteristics ◽  
Switching Loss ◽  
Trade Off ◽  
Switching Characteristics ◽  
Source Electrode

The effect of a gate trench bottom p+region (BPR) on the dynamic characteristics of 4H-SiC double-trench MOSFETs was investigated. Although employing a BPR led to an improved trade-off in the static characteristics, a BPR adversely affected the switching characteristics in spite of a reduction in the Miller capacitance compared to the case without a BPR.Simulation analysis revealed that a resistance between a BPR and a source electrode led to an increase in the switching loss. We have found reduction of the resistance is insufficient in order to provide benefits from the BPR. Hence, it is necessary to improve layouts of contacts of the BPR to the source electrode.

scholarly journals H∞ mixed sensitivity optimization for high speed tilting trains

2020 ◽  
Vol 9 (5) ◽  
pp. 1854-1860
Author(s):  
Fazilah Hassan ◽  
Argyrios Zolotas ◽  
Shaharil Mohd Shah
Keyword(s):  
Signal Processing ◽  
Fault Detection ◽  
Disturbance Rejection ◽  
High Speed ◽  
Important Research ◽  
Robust Controller ◽  
Trade Off ◽  
High Speed Trains ◽  
Simple Nature ◽  
Research Studies

The industrial norm of tilting high speed trains, nowadays, is that of Precedence tilt (also known as Preview tilt). Precedence tilt, although succesfull as a concept, tends to be complex (mainly due to the signal interconnections between vehicles and the advanced signal processing required for monitoring). Research studies of early prior to that of precedence tilt schemes, i.e. the so-called Nulling-type schemes, utilized local-per-vehicle signals to provide tilt action (this was essentially a typical disturbance rejection-scheme) but suffered from inherent delays in the control). Nulling tilt may still be seen as an important research aim due to the simple nature and most importantly due to the more straightforward fault detection compared to precedence schemes. The work in this paper presents a substantial extension conventional to robust H∞ mixed sensitivity nulling tilt control in literature. A particular aspect is the use of optimization is used in the design of the robust controller accompanied by rigorous investigation of the conflicting deterministic/stochastic local tilt trade-off 

scholarly journals Numerical Simulation Analysis of New Steel Sets Used for Roadway Support in Coal Mines

Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 606 ◽  
Author(s):  
Qinghai Li ◽  
Jingkai Li ◽  
Jinpeng Zhang ◽  
Changxiang Wang ◽  
Kai Fang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Theoretical Analysis ◽  
Simulation Analysis ◽  
Coal Mines ◽  
Soft Rock ◽  
Observation Point ◽  
Surrounding Rock ◽  
Surrounding Rock Control ◽  
Roadway Support ◽  
Two Sides

The surrounding rock control is a tough issue in the roadway with the swelling soft rock. The steel set is an important material for the control of swelling soft rock roadways. However, traditional steel sets failed to prevent the expansive pressure of the soft rock. Based on traditional steel sets, this paper developed a new steel set through both theoretical analysis and numerical simulation. The results showed that the new steel set was the set with the roof beam 1000 mm from the top of the set and the floor beam 400 mm from the bottom end of the set. The maximum deformations of the roof-floor and two sides of the ventilation roadway controlled by the best-improved set at the observation point were 147 mm and 108 mm, respectively. So, the best-improved set can effectively control the surrounding rock of the ventilation roadway. This provides an effective method for the surrounding rock control in extremely soft rock roadways.

A Method for Suppression of Pressure Pulses in Fluid-Filled Piping—Part I: Theoretical Analysis

1992 ◽  
Vol 114 (1) ◽  
pp. 60-65 ◽  
Author(s):  
Y. W. Shin ◽  
A. H. Wiedermann
Keyword(s):  
Theoretical Analysis ◽  
Pressure Pulse ◽  
Substantial Reduction ◽  
Pulse Height ◽  
Practical Interest ◽  
Nondestructive Method ◽  
Trade Off ◽  
Pressure Pulses ◽  
Fluid Jets ◽  
Pressure Surge

A simple, nondestructive method to suppress pressure pulses in fluid-filled piping is theoretically analyzed, and the result provides the basis needed for design and evaluation of a pressure-pulse suppression device based on the proposed theory. The method is based on forming of fluid jets in the event of a pressure surge, such that the pulse height and the energy of the pulse are reduced. The results for pressure pulses in the range of practical interest show that a substantial reduction in the pulse height can be attained, with accompanying reduction of the pulse remaining in the system. The analysis also reveals that a certain amount of trade-off exists in the design of the suppression device; a certain level of pulse energy remaining in the system must be accepted in order to keep the pulse height below a certain level, and vice versa.

Finite Element Numerical Simulation Analysis on Strengthening High Gravity Abutment Using Carbon Fiber Sheet

2011 ◽  
Vol 250-253 ◽  
pp. 1356-1359
Author(s):  
Zong Lin Wang ◽  
Li Hui Qin
Keyword(s):  
Carbon Fiber ◽  
Theoretical Analysis ◽  
Simulation Analysis ◽  
Experimental Models ◽  
High Gravity ◽  
Bridge Structure ◽  
Fiber Sheet ◽  
Finite Element Numerical Simulation ◽  
Strengthening Method ◽  
Carbon Fiber Sheet

Gravity abutment widely uses for substructure part of the bridge structure. For many reasons, there are many damages take place in the parts of abutment. The objective of this study is to evaluate the strengthening effects on the performance of highly structure of Gravity abutment. ANSYS ver.10 software is used in the theoretical analysis of capacity of abutment structure .There are two experimental models. The first model uses one ring of carbon fiber sheet and the second uses two rings of carbon fiber sheet .The results of theoretical analysis show that there are good effects when using carbon fiber sheet strengthening method.

Theoretical analysis of the influence of plane control network on lateral breakthrough error of long immersed tunnel

2020 ◽  
Vol 14 (3) ◽  
pp. 241-251
Author(s):  
Xinpeng Wang ◽  
Shengxiang Huang ◽  
Guanqing Li ◽  
Chenfeng Li ◽  
Wen Zhang
Keyword(s):  
Theoretical Analysis ◽  
High Precision ◽  
Simulation Analysis ◽  
Control Point ◽  
Control Network ◽  
Immersed Tunnel ◽  
Measurement Control ◽  
Engineering Practices ◽  
Rendezvous And Docking ◽  
Outer Plane

AbstractThere is extremely strict precision requirement for the lateral breakthrough error of long immersed tunnel in the offshore island and tunnel project, but the point location layout range of the outer plane control network is limited in the artificial island, and the space inside the tunnel is long and narrow, which is not conducive to high-precision through-measurement control. In order to further reduce the influence of the error of the plane control network on the lateral breakthrough error of the immersed tunnel, a mathematical model of the influence of the lateral breakthrough error caused by the orientation direction of the outer control point and the position of the breakthrough point has been established through the theoretical analysis in this study, and the favorable orientation directions and the favorable penetration point are analyzed. It is suggested through simulation analysis that the direction that is as consistent with that from the entrance (outlet) point to the penetration point as possible is as the advantageous orientation, which could minimize the lateral penetration error and ensure high-precision rendezvous and docking of the immersed tunnel. This study is instructive for similar engineering practices.

scholarly journals Theoretical Research and Numerical Simulation on Water Resistance Mechanism of Textile Bag in Water Passage

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Ang Li ◽  
Yuxuan Yang ◽  
Mingcheng Zhu ◽  
Wenzhong Zhang ◽  
Bingnan Ji ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Theoretical Analysis ◽  
Water Resistance ◽  
Simulation Analysis ◽  
Water Pressure ◽  
Water Inrush ◽  
Deformation Characteristics ◽  
Water Blocking ◽  
The Stability ◽  
Water Passage

It is an important problem in the mine water disaster prevention and control to control the large passage moving water. Traditional grouting technology is to put coarse aggregate and fine aggregate downward first and then grouting treatment. But the aggregate and cement flow distance is long, consumption is large, cost is high, and easy to appear secondary water inrush. Centering on the technical difficulties in the rapid construction of the blocking body of the moving water passage, a water-blocking textile bag was invented. The purpose of blocking the tunnel water inrush was achieved by grouting inside the bag body, which fundamentally realized the rapid blocking of the large passage through water under the condition of moving water. However, the mechanism, water plugging law, and design parameters of water blocking roadway with textile bag are still unclear. In this paper, the slip law and stability of the textile bag in the moving water and the deformation characteristics caused by the dynamic water pressure are theoretically analyzed and simulated. Through theoretical analysis, the ultimate antihydraulic stress value of a textile bag of a certain specification is calculated, and the parameters of the textile bag that affect the stability of the bag body are also determined. Xflow was used for numerical simulation analysis to study the deformation characteristics of the textile bag under water and the law of water barrier. The simulation analysis focuses on the water resistance effect and flow field distribution characteristics of the textile bag in the water passage under the condition of low flow rate and low pressure, as well as the stability and self-deformation characteristics of the textile bag under the condition of high flow rate and high pressure. The accuracy of the limit resistance to water pressure of the textile bag obtained from theoretical analysis is verified. The results show that the theoretical analysis is consistent with the simulation results. The textile bag can realize the fast controllable plugging of the large water passage of moving water within the limit of the antihydraulic stress.

scholarly journals Heterogeneous Gaussian Mechanism: Preserving Differential Privacy in Deep Learning with Provable Robustness

2019 ◽  
Author(s):  
NhatHai Phan ◽  
Minh N. Vu ◽  
Yang Liu ◽  
Ruoming Jin ◽  
Dejing Dou ◽  
...  
Keyword(s):  
Neural Networks ◽  
Deep Learning ◽  
Theoretical Analysis ◽  
Gaussian Noise ◽  
Deep Neural Networks ◽  
Differential Privacy ◽  
Trade Off ◽  
Adversarial Examples ◽  
Hidden Layer ◽  
Privacy Budget

In this paper, we propose a novel Heterogeneous Gaussian Mechanism (HGM) to preserve differential privacy in deep neural networks, with provable robustness against adversarial examples. We first relax the constraint of the privacy budget in the traditional Gaussian Mechanism from (0, 1] to (0, infty), with a new bound of the noise scale to preserve differential privacy. The noise in our mechanism can be arbitrarily redistributed, offering a distinctive ability to address the trade-off between model utility and privacy loss. To derive provable robustness, our HGM is applied to inject Gaussian noise into the first hidden layer. Then, a tighter robustness bound is proposed. Theoretical analysis and thorough evaluations show that our mechanism notably improves the robustness of differentially private deep neural networks, compared with baseline approaches, under a variety of model attacks.

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