The conventional Kalman filter is based on the assumption of non-delayed measurements. Several modifications appear to address this problem, but they are constrained by two crucial assumptions: 1) the delay is an inte...The conventional Kalman filter is based on the assumption of non-delayed measurements. Several modifications appear to address this problem, but they are constrained by two crucial assumptions: 1) the delay is an integer multiple of the sampling interval, and 2) a stochastic model representing the relationship between delayed measurements and a sequence of possible non-delayed measurements is known. Practical problems often fail to satisfy these assumptions, leading to poor estimation accuracy and frequent track-failure. This paper introduces a new variant of the Kalman filter, which is free from the stochastic model requirement and addresses the problem of fractional delay.The proposed algorithm fixes the maximum delay(problem specific), which can be tuned by the practitioners for varying delay possibilities. A sequence of hypothetically defined intermediate instants characterizes fractional delays while maximum likelihood based delay identification could preclude the stochastic model requirement. Fractional delay realization could help in improving estimation accuracy. Moreover, precluding the need of a stochastic model could enhance the practical applicability. A comparative analysis with ordinary Kalman filter shows the high estimation accuracy of the proposed method in the presence of delay.展开更多
Kinetics of thermal decomposition of benzene on lignite-derived char was investigated at 900℃ by applying a new method to continuously monitor the char surface activity.Benzene vapor was continuously forced to pass t...Kinetics of thermal decomposition of benzene on lignite-derived char was investigated at 900℃ by applying a new method to continuously monitor the char surface activity.Benzene vapor was continuously forced to pass through a micro fixed bed of char with residence time as short as 7.6 ms,and then detected continuously by a flame-ionization detector.Results showed the presence of two different types of char surfaces;consumptive Type I surface and non-consumptive(sustainable)Type II surface.Type I surface of a partially CO_(2)-gasified char had an capacity of carbon deposit from benzene over 20 wt%-char and an initial activity(represented by a first-order rate constant)as high as 160 s−1.Both of them decreased with increasing carbon deposit due to consumption of micropores accessible to benzene,and finally became zero leaving Type II surface that had a very stable activity with rate constant of 4 s−1.The chars without gasification had capacities of Type I surfaces smaller by two orders of magnitude than the partially gasified char,while the Type II surfaces had activities similar to that of the partially gasified char.It was found that Type II surface converted benzene into not only carbon deposit but also diaromatics and even greater aromatics.Composition of the greater aromatics was unknown because they were deposited onto the reactor wall immediately after passing through the char bed.展开更多
We propose a reliable asymmetric dual-k spacer with SiC source/drain（S/D）pocket as a stressor for a Si channel.This enhances the device performance in terms of electron mobility（eMobility）,current driving capabili...We propose a reliable asymmetric dual-k spacer with SiC source/drain（S/D）pocket as a stressor for a Si channel.This enhances the device performance in terms of electron mobility（eMobility）,current driving capabilities,transconductance（G_m）and subthreshold slope（SS）.The improved performance is an amalgamation of longitudinal tensile stress along the channel and reduced series resistance.We analysed the variation in drive current for different values of carbon（C）mole fraction y in Si_（1-y）C_y.It is found that the mole fraction also helps to improve device lifetime,performance enhancement also pointed by transconductance variation with the gate length.All the simulations are performed in the 3-D Sentaurus TCAD tool.The proposed device structure achieved ION=2.17 mA/μm for Si_（0.3）C_（0.7） and found that Si_（0.5）C_（0.5） is more suitable for the perspective of a process variation effect for 14 nm as the gate length.We introduce reliability issues and their solutions for Si（1-y）Cy FinFET for the first time.展开更多
In this paper, analysis of DC and analog/RF performance on cylindrical gate-all-around tunnel fieldeffect transistor（TFET） has been made using distinct device geometry. Firstly, performance parameters of GAATFET are...In this paper, analysis of DC and analog/RF performance on cylindrical gate-all-around tunnel fieldeffect transistor（TFET） has been made using distinct device geometry. Firstly, performance parameters of GAATFET are analyzed in terms of drain current, gate capacitances, transconductance, source-drain conductance at different radii and channel length. Furthermore, we also produce the geometrical analysis towards the optimized investigation of radio frequency parameters like cut-off frequency, maximum oscillation frequency and gain bandwidth product using a 3D technology computer-aided design ATLAS. Due to band-to-band tunneling based current mechanism unlike MOSFET, gate-bias dependence values as primary parameters of TFET differ. We also analyze that the maximum current occurs when radii of Si is around 8 nm due to high gate controllability over channel with reduced fringing effects and also there is no change in the current of TFET on varying its length from 100 to 40 nm.However current starts to increase when channel length is further reduced for 40 to 30 nm. Both of these trades-offs affect the RF performance of the device.展开更多
The application of Non-Orthogonal Multiple Access(NOMA) technology into satelliteaerial-ground integrated networks can meet the requirements of ultra-high rate and massive connectivity for the Sixth-Generation(6G) com...The application of Non-Orthogonal Multiple Access(NOMA) technology into satelliteaerial-ground integrated networks can meet the requirements of ultra-high rate and massive connectivity for the Sixth-Generation(6G) communication systems. We consider an uplink NOMA scenario for such a satellite-aerial-ground integrated network where multiple users communicate with satellite under the help of an Unmanned Aerial Vehicle(UAV) as an aerial relay equipped with a phased array. Supposing that buffer-aided decode-and-forward protocol is adopted at the UAV relay, we first formulate an optimization problem to maximize Ergodic Sum Rate(ESR) of the considered system subject to individual power constraint and quality-of-service constraint of each user.Then, with known imperfect channel state information of each user, we propose a joint power allocation and robust Beam Forming(BF) iterative algorithm to maximize ESR for the user-to-UAV link. Besides, to take the advantages of Free-Space Optical(FSO) and millimeter Wave(mmWave)communications, we present a switch-based hybrid FSO/mmWave scheme and a robust BF algorithm for the UAV-to-satellite link to achieve higher rate. Moreover, a closed-form ESR expression is derived. Finally, the effectiveness and correctness of the proposed solutions are verified by numerical simulations, and the performance evaluation results show that the proposed solutions not only achieve performance enhancement and robustness, but also outperform the orthogonal multiple access significantly.展开更多
基金supported by the Department of Science and Technology,Government of India under the Inspire Faculty Award
文摘The conventional Kalman filter is based on the assumption of non-delayed measurements. Several modifications appear to address this problem, but they are constrained by two crucial assumptions: 1) the delay is an integer multiple of the sampling interval, and 2) a stochastic model representing the relationship between delayed measurements and a sequence of possible non-delayed measurements is known. Practical problems often fail to satisfy these assumptions, leading to poor estimation accuracy and frequent track-failure. This paper introduces a new variant of the Kalman filter, which is free from the stochastic model requirement and addresses the problem of fractional delay.The proposed algorithm fixes the maximum delay(problem specific), which can be tuned by the practitioners for varying delay possibilities. A sequence of hypothetically defined intermediate instants characterizes fractional delays while maximum likelihood based delay identification could preclude the stochastic model requirement. Fractional delay realization could help in improving estimation accuracy. Moreover, precluding the need of a stochastic model could enhance the practical applicability. A comparative analysis with ordinary Kalman filter shows the high estimation accuracy of the proposed method in the presence of delay.
基金A part of this work was financially supported by New Energy and Industrial Technology Development Organization,Japan,for an R/D project on next-generation coal gasification system.Another part was supported by the Japan Society for the Promotion of Science(JSPS)for Grant-in-Aid for Scientific Research(Grant 17H01340).
文摘Kinetics of thermal decomposition of benzene on lignite-derived char was investigated at 900℃ by applying a new method to continuously monitor the char surface activity.Benzene vapor was continuously forced to pass through a micro fixed bed of char with residence time as short as 7.6 ms,and then detected continuously by a flame-ionization detector.Results showed the presence of two different types of char surfaces;consumptive Type I surface and non-consumptive(sustainable)Type II surface.Type I surface of a partially CO_(2)-gasified char had an capacity of carbon deposit from benzene over 20 wt%-char and an initial activity(represented by a first-order rate constant)as high as 160 s−1.Both of them decreased with increasing carbon deposit due to consumption of micropores accessible to benzene,and finally became zero leaving Type II surface that had a very stable activity with rate constant of 4 s−1.The chars without gasification had capacities of Type I surfaces smaller by two orders of magnitude than the partially gasified char,while the Type II surfaces had activities similar to that of the partially gasified char.It was found that Type II surface converted benzene into not only carbon deposit but also diaromatics and even greater aromatics.Composition of the greater aromatics was unknown because they were deposited onto the reactor wall immediately after passing through the char bed.
基金the M.P.Council of Science & Technology,Bhopal,India,for financial support under the R&D project scheme No:1950/CST/R&D/Phy & Engg Sc/2015:27~(th) Aug 2015
文摘We propose a reliable asymmetric dual-k spacer with SiC source/drain（S/D）pocket as a stressor for a Si channel.This enhances the device performance in terms of electron mobility（eMobility）,current driving capabilities,transconductance（G_m）and subthreshold slope（SS）.The improved performance is an amalgamation of longitudinal tensile stress along the channel and reduced series resistance.We analysed the variation in drive current for different values of carbon（C）mole fraction y in Si_（1-y）C_y.It is found that the mole fraction also helps to improve device lifetime,performance enhancement also pointed by transconductance variation with the gate length.All the simulations are performed in the 3-D Sentaurus TCAD tool.The proposed device structure achieved ION=2.17 mA/μm for Si_（0.3）C_（0.7） and found that Si_（0.5）C_（0.5） is more suitable for the perspective of a process variation effect for 14 nm as the gate length.We introduce reliability issues and their solutions for Si（1-y）Cy FinFET for the first time.
基金supported by the Council of Scientific and Industrial Research(CSIR)Funded Research Project,Grant No.22/0651/14/EMR-II,Government of India
文摘In this paper, analysis of DC and analog/RF performance on cylindrical gate-all-around tunnel fieldeffect transistor（TFET） has been made using distinct device geometry. Firstly, performance parameters of GAATFET are analyzed in terms of drain current, gate capacitances, transconductance, source-drain conductance at different radii and channel length. Furthermore, we also produce the geometrical analysis towards the optimized investigation of radio frequency parameters like cut-off frequency, maximum oscillation frequency and gain bandwidth product using a 3D technology computer-aided design ATLAS. Due to band-to-band tunneling based current mechanism unlike MOSFET, gate-bias dependence values as primary parameters of TFET differ. We also analyze that the maximum current occurs when radii of Si is around 8 nm due to high gate controllability over channel with reduced fringing effects and also there is no change in the current of TFET on varying its length from 100 to 40 nm.However current starts to increase when channel length is further reduced for 40 to 30 nm. Both of these trades-offs affect the RF performance of the device.
基金co-supported by the Key International Cooperation Research Project,China(No.61720106003)Jiangsu Province Science and Technology Project,China(No.BE2021031)+4 种基金the Shanghai Aerospace Science and Technology Innovation Foundation,China(No.SAST2019-095)NUPTSF(No.NY220111)the Research Project of Science and Technology on Complex Electronic System Simulation Laboratory,China(No.DXZT-JC-ZZ-2019-009)the National Natural Science Foundation of China(No.61801234)the Postgraduate Research and Practice Innovation Program of Jiangsu Province,China(No.KYCX210739)。
文摘The application of Non-Orthogonal Multiple Access(NOMA) technology into satelliteaerial-ground integrated networks can meet the requirements of ultra-high rate and massive connectivity for the Sixth-Generation(6G) communication systems. We consider an uplink NOMA scenario for such a satellite-aerial-ground integrated network where multiple users communicate with satellite under the help of an Unmanned Aerial Vehicle(UAV) as an aerial relay equipped with a phased array. Supposing that buffer-aided decode-and-forward protocol is adopted at the UAV relay, we first formulate an optimization problem to maximize Ergodic Sum Rate(ESR) of the considered system subject to individual power constraint and quality-of-service constraint of each user.Then, with known imperfect channel state information of each user, we propose a joint power allocation and robust Beam Forming(BF) iterative algorithm to maximize ESR for the user-to-UAV link. Besides, to take the advantages of Free-Space Optical(FSO) and millimeter Wave(mmWave)communications, we present a switch-based hybrid FSO/mmWave scheme and a robust BF algorithm for the UAV-to-satellite link to achieve higher rate. Moreover, a closed-form ESR expression is derived. Finally, the effectiveness and correctness of the proposed solutions are verified by numerical simulations, and the performance evaluation results show that the proposed solutions not only achieve performance enhancement and robustness, but also outperform the orthogonal multiple access significantly.
