Feedback Path Research Articles

Second Harmonic Current Reduction Control for Two-Stage Inverter with a New Inductor Current Feedback Path

The instantaneous output power of the two-stage inverter pulsates at twice the output frequency, resulting in the second harmonic current (SHC) in the front-end dc-dc converter. To reduce the SHC in the inductance branch while maintaining good dynamic performance, this paper proposes a control scheme based on a new inductor current feedback path in the front-end buck converter. In the scheme, through the equivalent gain, the virtual resistor, and the bandpass filter, the inductor current is fed to the front of the voltage regulator. The feedback function simplification is studied and the implementation of the proposed scheme is illustrated. With considerations of both reducing the SHC and improving the dynamic performance, the parameter design approach for the feedback function is also presented for the proposed SHC reduction control scheme, and the performance analysis and comparison from the viewpoint of output impedance are provided. The simulation model and the prototype of a 10 kW two-stage inverter are constructed. The simulation and experimental results about the low SHC in the front-end buck converter and the fast dynamic response during the load transient verify the effectiveness of the proposed scheme.

A general and efficient clocking scheme for majority logic in quantum-dot cellular automata

Quantum-dot cellular automata (QCA) is a nanotechnology with characteristics of high speed, high density, and low power consumption to be one of the strong alternatives to replace traditional CMOS in the future in theory. Its primitive is a majority gate, instead of AND/OR logic in CMOS, which can reduce the complexity of a system and thus its overhead. In this paper, a general and efficient clocking scheme to facilitate the design of circuits using majority gates in QCA is proposed as their scale extends. Each clock zone in this scheme is an octagon adjacent to the other three zones. This results in four input and two output directions in clock zones 0 and 2 to design circuits with majority gates, two input and four output directions in clock zones 1 and 3 to improve the flexibility of circuit routing. Besides, this scheme utilizes the flexible feedback paths for sequential circuits, equivalent clock zones, and elastic QCA wires for efficiently wiring circuits. This paper then takes a one-bit full adder and an SR-latch as examples to show the generality and efficiency of the proposed clocking scheme in designing combinational and sequential circuits, respectively. An arithmetic unit is also taken as an example to illustrate its high expansibility in designing larger circuits. Experimental results show that the proposed clocking scheme is more suitable for QCA circuit design in contrast to previous clocking schemes.

LCL‐filter resonance suppression in grid‐connected inverter based on strictly real positive plant strategy

AbstractResonance is one of the most significant challenges in a voltage source inverter interfaced with the grid through an LCL filter. The capacitor current (CC) damping control methodology is considered due to its high‐quality of grid injected current feature. It is widely accepted that the proportional CC feedback compensation damping method becomes ineffective at critical resonance frequency due to control loop delays and may result in an unstable system under grid impedance or filter parameters variations. A suitable differential compensator placed in the CC feedback path can address this issue with a trade‐off between robustness and noise rejection capability. This paper offers a different design method called parallel feedforward compensation (PFC) method, which builds an almost strictly real positive (ASRP) plant and realized damping with enhanced stability features. In the proposed alternative, a compensator consisting of a damping gain and a sampled delay is placed across the filter plant and filter CC feedback loop and the joint output of this augmented plant is then transmitted back at the reference point on the input side of the inverter to attenuate the undesirable resonance peak. The control response and stability performance analysis show that the suggested methodology offers a wide damping region, high robustness, and improved control performance. Simulation and experimental results are presented to confirm the theoretical findings.

Agile offset frequency locking for single-frequency fiber lasers

Single frequency fiber lasers (SFFLs) have seen increasing applications in state-of-the-art quantum technologies, which usually require precise and stable offset frequency locking (OFL). However, limited by the piezoelectric transducer bandwidth in SFFLs and the loop bandwidth of the OFL, the large-gap jumping between two locked offset frequencies will take an undesirable amount of time. In order to diminish that consuming time, we developed an agile offset frequency locking system based on a hybrid loop of a feed-forward path and a feedback path. In accordance with the experimental demonstration, we characterized the performances of the offset frequency locking system, as frequency-locking stability with an Allan deviation of 3.2 × 10−14 at 1 s averaging time and jumping agility with a duration of 0.6 ms at 1.3 GHz frequency gap, which is a factor of 60 faster than that without the feed-forward path. This mechanism can find direct applications in existing quantum metrology experiments with SFFLs where high-speed frequency jumping or sweeping is needed.

A Reconfigurable Balun-LNA and Tunable Filter With Frequency-Optimized Harmonic Rejection for Sub-GHz and 2.4 GHz IoT Receivers

A CMOS reconfigurable balun-LNA and tunable filter is proposed for sub-GHz and 2.4 GHz IoT applications. The core of the LNA gain stage is composed of two cascaded inverters for the single-to-differential conversion, and the additional inverter is placed in the feedback path for the implementation of the active feedback. In the sub-GHz band, it operates as an active feedback LNA by enabling all inverter stages. At the narrow 2.4 GHz band, it operates as an inductive source degenerated LNA (ISDLNA) with a minimum noise figure (NF) by disabling the inverter in the feedback path. In order to suppress the unwanted local oscillator (LO) harmonic mixing in the sub-GHz band and provide the frequency-optimized harmonic rejection ratio (HRR), a reconfigurable Sallen-Key (SK) filter-based <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4^{\mathbf {th}}$ </tex-math></inline-formula> -order tunable filter is proposed on the basis of the modified super source follower (SSF) with enhanced loop gain. It covers the entire VHF band with a smaller capacitance tuning ratio by switching the polarity of the output of the modified SSF. Compared to previous works, this work provides the largest tuning range from 50 MHz to 700 MHz without splitting individually optimized circuits corresponding to each frequency band and using no external board components. This is the first suggestion of a fully integrated SK filter-based tunable filter to cover VHF/UHF bands through a hardware re-configurability without increasing the tuning ratio of the switched capacitor array, while providing an optimum HRR performance for corresponding operating frequencies in conjunction with harmonic rejection mixer (HRM). In addition, it proposes a hardware efficient re-configurable balun-LNA to operate as a wideband feedback LNA at sub-GHz and a narrowband ISDLNA at 2.4 GHz without the use of external input matching circuits. In the measurement, the proposed front-end achieves an average power gain ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{S}_{{21}}$ </tex-math></inline-formula> ) of 25.9 dB, NF of < 4.25 dB, and in-band input-referred third-order intercept point (IIP3) of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$&gt;\!\!\!-12.8$ </tex-math></inline-formula> dBm over the tuning range from 50 MHz to 700MHz. The proposed tunable filter shows the frequency-optimized HRR from 10 dBc to 26 dBc over the tuning range while greatly reducing a silicon area. At 2.4 GHz band, it shows <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{S}_{{21}}$ </tex-math></inline-formula> of 14.7 dB, NF of 3.2 dB, and in-band IIP3 of −4.5 dBm. The die area of the proposed circuit, excluding I/O PADs and the measurement output buffer, is less than 2.0 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . The power consumption of the front-end working at sub-GHz and 2.4 GHz bands is 33.6 mW and 5.1 mW respectively.

Calender barring review with experiences

Excessive calender vibration affects all styles of calender stacks from single to multi-nip, all hard rolls, or a combination of hard and soft rolls. Calender vibration can be forced vibration or self-excited vibration. Forced vibration occurs at the first few harmonics of the calender roll rotational speeds and is caused by imbalance, misalignment, eccentricity, etc. Self-excited vibration, the focus of this paper, occurs at higher frequencies. Feedback paths for self-excited vibration must be understood in order to ameliorate the problem. This is presented in the context of the historical development of the theory of self-excited feedback mechanisms, followed by a survey of self-excited feedback mechanisms in various types of calender stacks. Methodology to determine which feedback path is present and techniques to control or eliminate the resulting vibration follow. To obtain a flavor of the types of problems faced and practical remedial actions, a variety of experiences with barring issues are provided.

Phase Feedforward Damping Control Method for Virtual Synchronous Generators

Damping control plays an important role in suppressing the oscillation modes of virtual synchronous generators (VSGs). The most widely used damping control method through a frequency deviation feedback path is confronted with multiple challenging inherent contradictions among the different control objectives, resulting in seriously degraded control performance of VSGs. To resolve these contradictions fundamentally, this article proposes a novel phase feedforward damping (PFD) control method for VSG from the perspective of restructuring the damping controller. It replaces the traditional frequency deviation feedback path with a novel damping controller utilizing a phase feedforward path. Then, considering the grid-connected and islanding operation modes, respectively, a detailed comparative study of the traditional damping-based VSG (Tra-VSG) and the PFD-based VSG (PFD-VSG) is conducted. Both the theoretical and experimental results demonstrate convincingly that the proposed PFD control method can reconcile the different control objects of VSG, and thus, compared with Tra-VSG, PFD-VSG exhibits vastly superior response performance of the active power and the frequency in both grid-connected and islanding operation modes.

An Area-Optimized and Power-Efficient CBC-PRESENT and HMAC-PHOTON

This paper introduces an area-optimized and power-efficient implementation of the Cipher Block Chaining (CBC) mode for an ultra-lightweight block cipher, PRESENT, and the Keyed-Hash Message Authentication Code (HMAC)-expanded PHOTON by using a feedback path for a single block in the scheme. The proposed scheme is designed, taped out, and integrated as a System-on-a-Chip (SoC) in a 65-nm CMOS process. An experimental analysis and comparison between a conventional implementation of CBC-PRESENT/HMAC-PHOTON with the proposed feedback basis is performed. The proposed CBC-PRESENT/HMAC-PHOTON has 128-bit plaintext/text and a 128-bit secret key, which have a gate count of 5683/20,698 and low power consumption of 1.03/2.62 mW with a throughput of 182.9/14.9 Mbps at the maximum clock frequency of 100 MHz, respectively. The overall improvement in area and power dissipation is 13/50.34% and 14.87/75.28% when compared to a conventional design.

A 1–3 GHz CMOS mixer-first receiver frontend with dual-feedback OTA achieving 306 MHz IF bandwidth, 2.1 dB NF, and 33 dB gain

In this paper, a mixer-first receiver frontend with dual-feedback baseband is proposed. The negative resistive and positive capacitive feedback paths are both applied to single-stage inverter-based operational transconductance amplifier (OTA) with fewer poles, to cover a wide BB frequency range. The [Formula: see text]-path filtering at the RF side and second-order filtering at the BB side inhibit out-of-band blocker interferences. The receiver frontend is designed in 65 nm CMOS. Simulation results display an NF of 2.1 dB across 306 MHz IF bandwidth, and a maximum gain of 33 dB from 1 to 3 GHz LO frequency range. The in-band and out-of-band IIP3 are -13 and 16 dBm, respectively. The receiver core draws 40 mW at 1 GHz LO frequency.

Experimental real-time GbE MIMO FSO under fog conditions with software defined GNU Radio platform-based adaptive switching

In this paper, we demonstrate the first, to our knowledge, experimental implementation of a gigabit Ethernet multiple input single output free space optical (FSO) communications link using adaptive switching implemented in the software defined open-source software, GNU Radio, and analyze its performance. A fully functional FSO link with a feedback path is implemented using cost effective off-the-shelf components, i.e., media converters and small form-factor pluggable modules. We propose a switching mechanism at the transmitter to improve the link performance under different fog conditions and provide results for the proposed FSO system compared with a single FSO link. The real-time channel estimation is demonstrated and, based on the channel state information, adaptive switching is carried out in GNU Radio. We show that the proposed system under the heavy fog condition offers almost the same packet error rate under the clear channel but with a reduced data rate by about 100 Mbps (i.e., 600 Mbps).

What Drives Smallholders to Utilize Socialized Agricultural Services for Farmland Scale Management? Insights from the Perspective of Collective Action

The diseconomies of scale found in smallholders’ agricultural production is a common problem faced by global agricultural development. Notable examples of regions in which this occurs include Central and Eastern Europe, India, Brazil, and China. Smallholders usually differ in their demands for socialized agricultural services due to scattered farmland, various soil conditions, different selections of crop varieties, and diverse farming arrangements. Such differences make it difficult for smallholders to cooperate on farmland scale management, resulting in a collective action dilemma. Based on the Institutional Analysis and Development framework, this paper provides insights into the influencing factors and effects of smallholders’ utilization of socialized agricultural services and constructs a cooperative mechanism for the purpose of solving the collective action dilemma in rural areas of China. We found that household characteristics, biophysical conditions, attributes of community, and rules-in-use jointly generate the action situation in the process of smallholders’ cooperative utilization of agricultural socialized services. Among them, the rules-in-use not only have a direct impact on the action situation but also regulate the role of the other three sets of factors. Various factors and mechanisms affecting the cooperative utilization of socialized agricultural services by smallholders interact in the action arena and finally form relevant outcomes that can deal with the diseconomies of farmland fragmentation. These outcomes will be fed back to each external variable again along the feedback path, so as to promote the system and create a virtuous circle. This study provides a theoretical contribution to understanding smallholders’ cooperation in the process of agricultural large-scale operation, especially in regions and countries with a large number of smallholders.

Discrete‐time current regulator with arbitrary poles placement for alternating current machines

To pursue high-performance motor drive, the current regulators are designed directly in the discrete domain. However, few kinds of research are developed to achieve arbitrary poles placement simply. To fill this gap, the authors propose a discrete-time current regulator consisting of two parts: the main regulator used to obtain decoupling control of dq axes currents, and the bi-proper compensator applied to realise arbitrary poles placement. To strengthen the anti-disturbance ability of the current regulator, the active resistance is added to the inner feedback path. Combining the active resistance, a new zero-order-hold equivalent motor model is developed, based on which the main regulator is designed using the zero-pole cancellation method. Furthermore, in this way, decoupling control for the two control objectives of reference tracking and anti-disturbance is realised. To achieve fast tracking response and negligible overshoot, an easy-to-implement scheme that simplifies the tuning of the current regulator is proposed based on the arbitrary poles placement. Moreover, the current regulator can be treated as a two-degree-of-freedom controller with this scheme. Finally, the effectiveness and reliability of the proposed current regulator are validated by the simulation results and experimental results in an alternating current machine drive platform.

Adaptive Control With Guaranteed Transient Behavior and Zero Steady-State Error for Systems With Time-Varying Parameters

It is nontrivial to achieve global zero-error regulation for uncertain nonlinear systems. The underlying problem becomes even more challenging if mismatched uncertainties and unknown time-varying control gain are involved, yet certain performance specifications are also pursued. In this work, we present an adaptive control method, which, without the persistent excitation (PE) condition, is able to ensure global zero-error regulation with guaranteed output performance for parametric strict-feedback systems involving fast time-varying parameters in the feedback path and input path. The development of our control scheme benefits from generalized <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$t$</tex> -dependent and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$x$</tex> -dependent functions, a novel coordinate transformation and “congelation of variables” method. Both theoretical analysis and numerical simulation verify the effectiveness and benefits of the proposed method.

Analysis and Suppression of Oscillation in V/F Controlled Induction Motor Drive Systems

V/F control has been widely applied for induction motor drive systems because of its simplicity and reliability. However, sustained oscillation often occurs under light load, which leads to undesirable faults. This article focuses on the causes of oscillation and proposes an oscillation suppression solution. Based on the small-signal model, an open-loop transfer function of the induction motor is derived. The resonant peak, which is related to system parameters, such as frequency and inertia, is obtained from the transfer function and leads to unstable regions. The oscillation effects are discussed in detail. Then, the current feedback compensation method without any motor parameter is proposed to suppress the oscillation by decreasing the resonant peak. The feedback gain is optimized and designed. Finally, three current feedback paths are tested and compared in simulation and experiment. Simulation and experimental results have demonstrated the correctness of the theoretical analysis and the effectiveness of the proposed methods. The feedback path from current to voltage in the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$d$ </tex-math></inline-formula> -axis is the best suppression solution for its wider gain range and higher stability in the application.

A Fractional-N Digital LC-PLL Using Coupled Frequency Doubler With Frequency-Tracking Loop for Wireline Applications

This article presents a 23.9–29.4 GHz digital <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> -phase-locked loop (PLL) architecture with a low phase noise (PN) and power-efficient coupled frequency doubler for 224 Gb/s PAM-4 transmitter clocking. The proposed frequency doubler is designed with two oscillators running at 14 and 28 GHz which are coupled by a transformer. Compared to a conventional frequency doubler or a two-way coupled oscillator, the coupling between the 14 and 28 GHz oscillators provides extra PN reduction as the 14 GHz oscillator can achieve lower PN than the 28 GHz one. In addition, by stacking the two oscillators through the transformer, the current is reused and hence power consumption is reduced. To optimize the PN performance across process, voltage, and temperature (PVT), a compact and power-efficient frequency-tracking loop (FTL) is implemented. The 14 GHz oscillator output is fed to the PLL feedback divider rather than the doubled output, which enables power saving in the prescaler divider in the feedback path. The proposed PLL is fabricated in 10 nm FinFET technology and the PLL achieves a 65 fs random jitter at the transmitter output after a 1st-order 4 MHz-BW CDR filtering which enables the industry’s first 224 Gb/s PAM-4 transmitter. Compared with a reference NMOS-GM <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> -digitally controlled oscillator (DCO) implemented on the same die, the proposed coupled frequency doubler achieves 4.75 dB lower PN with only a 25% power consumption increase. The <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> -PLL consumes 17.1 mW from a 0.8/1.0 V regulated supply and occupies an area of 0.088 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .

Thyroid Biokinetics for Radioactive I-131 in Twelve Thyroid Cancer Patients via the Refined Nine-Compartmental Model

The thyroid biokinetic model of radioactive I-131 was re-evaluated using a refined nine-compartmental model and applied to twelve thyroid cancer patients. In contrast to the simplified four-compartmental model regulated by the ICRP-56 report, the revised model included nine compartments specified in the ICRP-128 report, namely, oral, stomach, body fluid, thyroid, whole body, liver, kidney, bladder, and remainder (i.e., the whole body minus kidney and bladder). A self-developed program run in MATLAB was designed to solve the nine first-order simultaneous linear differential equations. The model was realized in standard and simplified versions. The latter neglected two feedback paths (body fluid to oral, i31, and kidney to the whole body, i87) to reduce computations. Accordingly, the biological half-lives for the major compartments (thyroid and body fluid + whole body) were 36.00 ± 15.01, 15.04 ± 5.63, 34.33 ± 15.42, and 14.83 ± 5.91 of standard and simplified version. The correlations between theoretical and empirical data for each patient were quantified by the dimensionless AT (agreement) index and, the ATtot index integrated each individual AT of a specific organ of one patient. Since small AT values indicated a closer correlation, the obtained range of ATtot (0.048 ± 0.019) proved the standard model’s reliability and high accuracy, while the simplified one yielded slightly higher ATtot (0.058 ± 0.023). The detailed outcomes among various compartments of twelve patients were calculated and compared with other researchers’ work. The correlation results on radioactive I-131 evolution in thyroid cancer patients’ bodies are instrumental in viewpoint of radioactive protection of patients and radiological personnel.

Three dimensional vibroacoustic topology optimization of hearing instruments using cut elements

The focus of this article is on level set based topology optimization of vibroacoustic hearing instruments. The goal is to demonstrate the applicability of the proposed framework for optimization of 3D industrial scale hearing instruments. The framework employs an immersed boundary cut element method to handle the modeling of complex design geometries on fixed unstructured meshes. Utilization of unstructured meshes allows for optimizing small parts of a complex hearing instrument without disturbing the overall geometry. The remaining parts of the model which are not included in the optimization process are modeled with segregated approach. The design parameterization is based on an explicit level set approach, for which the nodal level set values are linked to the mathematical design variables. The optimization problem is solved using mathematical programming and the sensitivities are obtained with a discrete adjoint approach. A validation study is carried out comparing the proposed cut element model to a body fitted mesh for a large range of frequencies. The optimization framework is then applied on the tube and the suspension structures of a hearing instrument system considering two sets of material properties for the design parts. The optimization considers the minimization of sound pressure on the microphone surface for discrete frequencies aiming to reduce the feedback paths and to increase the amplification that the device can deliver to the user. Both optimization cases improve the performance of the hearing instrument system by effectively reducing the sound pressure on the microphone surface for the considered frequency range.

A Quantization Noise Reduction Method for Delta-Sigma Fractional-N PLLs Using Cascaded Injection-Locked Oscillators

This paper describes an efficient way to reduce the quantization noise of delta-sigma fractional-N PLLs by using an injection-locked oscillator (ILO) in the feedback path. For further noise reduction, the use of cascaded ILOs is proposed. Behaving like a type-I high-order PLL, the cascaded ILOs effectively suppress the quantization noise like a high-order phase-domain low-pass filter (PDLPF). We show that the proposed ILO-based PDLPF significantly improves the out-of-band phase noise for wideband fractional-N PLLs as well as the in-band phase noise for fractional-N bang-bang PLLs (BBPLLs). Post-layout simulation results show that a ΔΣ fractional-N BBPLL with a 3-stage ILO can achieve the in-band noise reduction of 25 dB without having a nested PLL.

Öğrenenlerin E-Değerlendirmeye Dayalı Kişiselleştirilmiş Geri Bildirim Yollarının İncelenmesi

Purpose: The purpose of the research is to investigate personalized feedback paths of learners based on e-assessment according to the feedback preferences of learners and their needs. Methodology: The design-based research method consisting of two stages was used in this study. The study group comprised of 36 undergraduates in the department of Computer and Instructional Technology in the Education Faculty in one of the state universities was determined based on criterion sampling method. The data collection process has carried out with the same study group at both design stages by using blended learning method. Data collection tools are consisted of Motivation and Metacognition scales, learning management system records and semi-structured interview form. The descriptive analysis methods, Chi-Square independence test, multiple correspondence analysis, and content analysis have been used for data analysis. Findings: According to the findings of the research, the effect of test anxiety and extrinsic goal orientation from motivation sources, metacognition, the judgment of learning and task level variables have determined on feedback preferences of the learner. Classify by these characteristics, a number of personalized feedback strategies have been developed based on the learner's preferences and needs for feedback. In addition, it was found that learners wanted to get feedback from teachers rather than peers because they found teacher’s feedback more qualified and they did not trust their peers' feedback. Highlights: In order to use the personalized feedback strategies developed in the research in different research groups and training programs, it should be important that the system is similar to those in this study. These should be similar systems that determine both the learner's preference and the needs for feedback according to the learner characteristics to support learning performance. Otherwise, it is thought that will be out of the context of personalization.

Double-node-upset aware SRAM bit-cell for aerospace applications

In aerospace applications, the continuous scaling of CMOS technology makes SRAM cells more and more susceptible to soft errors. To overcome this issue, a radiation-hardened-based (RHBD) 13T SRAM cell has been proposed in this paper. The proposed cell has several benefits over other standard RHBD cells. The proposed cell can not only recover from SNUs induced at any of its sensitive nodes but also from DNUs induced at any of its sensitive node pairs. It has the lowest hold, total power cost, the highest critical charge, moderate area overhead, and better stability. To improve speed, the proposed cell uses a unique feedback path among its internal nodes. Finally, the figure of merit (FOM), SNU probability of failure (POF) comparison of cells validate that the proposed cell is a better choice for sub-nanometer aerospace applications.