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The droplet size significantly affects the performance of aerial spraying operations. Thus, it is crucial to develop rotary nozzles for helicopter spraying operations and analyze the influence of droplet size. We conducted a calibration test of the nozzle rotation speed to analyze the effects of air velocity, blade installation angle, hub diameter, and blade length on the rotation speed. The results showed that the rotation speed increased with an increase in air velocity and nozzle diameter and decreased with an increase in the blade angle. The rotation speed of three types of rotary nozzles was measured in the range of 576–15 358 r/min. A high-speed wind tunnel test was conducted to determine the droplet size of the rotary nozzles at different rotation speeds, spray flow rates, and hub mesh numbers. The influence degree of the three factors on the droplet size was rotation speed > spray flow rate > mesh number. The multiple linear regression equation of the volume median diameter (VMD) of the droplet size was obtained. The droplet size obtained from wind tunnel and flight tests at 5000 and 7000 r/min was compared. The droplet size was in the range of 148.56–259.39 μm and was slightly larger under wind tunnel conditions than during the flight test. The relative width of the droplet spectrum was small for both test methods, indicating that the droplet size distribution of the three rotary nozzles was uniform. Finally, the spray nozzles were used for insect control in forest areas and achieved a control efficiency of 94.6. This study provides a reference for optimizing the operating parameters of spraying nozzles and improving the performance of helicopter-based low-volume spraying operations. [Display omitted] • We developed a rotary nozzle for manned helicopter spraying operations. • The influence degree of the three factors on the droplet size was rotation speed > spray flow rate > mesh number. • The multiple linear regression equation of the droplet size was obtained. • The spray nozzles were used for insect control in forest areas and achieved a control efficiency of 94.6. [ABSTRACT FROM AUTHOR]

Fuel cell distributed drive electric tractors (FCDET) are one of the necessary means to achieve truly green agriculture. However, low traction efficiency, poor control coordination, and excessive energy consumption are the main reasons hindering the industrialization of FCDET. This paper proposed a parametric collaborative optimization design method and innovative verification system that considers the drive system and energy system. Based on the tractor plowing operating conditions, a 7-DOF coupled dynamics model of the distributed drive system and a tire-soil interaction model were established, and the key component selection and parameter matching were completed. On the drive system optimization level, the front and rear wheelside transmission ratios are optimized based on a multi-island genetic algorithm (MIGA). On the energy system optimization level, the globally optimal power distribution ratio is found based on the dynamic programming algorithm (DP). A complete experimental prototype verification system is constructed based on the MATLAB/Simulink-NI PXI joint simulation platform, physical prototype test bench, and real vehicle multi-index test platform. The results show that the average efficiencies of the optimized drive and energy system are increased by 0.38 % and 3.82 %, the total energy consumption (total hydrogen consumption) is reduced by 25.40 % and 15.39 %, respectively. The maximum fault-free operating time is 5.5h, the average traction power is 21.07 kW, and the average traction force is 10610 N in the all-wheel drive mode. The experimental results fully demonstrate that the electric tractor with the fuel cell distributed drive system as the core can meet the verification of multiple indicators. This study can provide a new theoretical basis and technical verification method for the optimal design and system control of fuel cell distributed drive electric tractors. • Parameter collaborative optimization of drive system and energy system. • Tractor multi-body dynamics model and tire-soil interaction model. • Multi-island genetic algorithm and dynamic programming algorithm. • MATLAB/Simulink-NI PXI joint simulation test, physical prototype test and real vehicle multi-indicator test. • Innovative verification method combining theoretical and experimental. [ABSTRACT FROM AUTHOR]

• A single neural network parameter extractor for BSIM-CMG IV and CV model is developed. • A global I-V and C-V parameter extraction for a large range of gate length is achieved. • A high fitting accuracy is demonstrated on TCAD simulated data calibrated to 10 nm node. A global I-V and C-V BSIM-CMG parameter extraction methodology based on deep learning is proposed. 100 k training datasets were generated through Monte Carlo simulation varying 28 IV and CV model parameters in the industry-standard BSIM-CMG FinFET model. For each of the 100 k Monte Carlo-selected BSIM-CMG parameter dataset, the I D -V G and C GG -V G characteristics of seven Monte Carlo-selected gate lengths ranging from 14 nm to 110 nm were generated as the input to train the parameter extraction neural network. The neural network outputs for training are the 28 model parameters' values. The neural network's capability to extract BSIM-CMG model parameters that accurately fit TCAD-generated I D -V G and C GG -V G data over a range of gate lengths was demonstrated. This marks the first time a deep learning compact model parameter extraction flow, employing a single neural network for both I-V and C-V parameters and for a range of gate length, is presented. [ABSTRACT FROM AUTHOR]

• A RRAM compact model compatible with OxRAM and CBRAM. • Accurately model experimental DC and transient data of various RRAM structures. • RRAM variation and disturb effect are modeled. • Compatible with SPICE simulation and memory circuit designs. We present a versatile compact model for resistive random-access memory (RRAM) that can model different types of RRAM devices such as oxide-RRAM (OxRAM) and conducting-bridge-RRAM (CBRAM). The model unifies the switching mechanisms of these RRAMs into a single framework. We showcase the model's accuracy in reproducing published experimental device DC and transient characteristics of various RRAM structures. We also demonstrate the model's efficacy in capturing RRAM variability and conducting 1T1R circuit simulations. [ABSTRACT FROM AUTHOR]

A spacer lithography technology using a sacrificial layer and a chemical vapor deposition (CVD) spacer layer has been developed, and is demonstrated to achieve sub-40 nm structures with conventional dry etching. The minimum-sized features are finished not by photolithography but by the CVD film thickness. Therefore the spacer lithography technology yields critical dimension variations of minimum-sized features which are much smaller than achieved by optical or e-beam lithography. It also provides a doubling of device density for a given lithography pitch. This spacer lithography technology is used to pattern silicon-fin structures for double-gate MOSFETs and CMOS FinFET results are reported. [Copyright &y& Elsevier]

• Negative capacitance (NC) may enable gate-all-around FET scaling beyond 0.5 nm node. • 3-D Ginzburg-Landau-Khalatnikov model is adopted in the TCAD simulation. • The parameters of ferroelectric are extracted from an experimental C-V result. • The NC benefits are retained over a varying set of ferroelectric parameters. We present a TCAD simulation of the negative capacitance gate-all-around (NCGAA) field-effect transistor with the 3-D Ginzburg-Landau-Khalatnikov Model. The baseline device is based on the 2020 IRDS Table, and the mobility model is calibrated to account for ballistic transport and to match the "1.5 nm node" IRDS on-current requirement. The NC parameters are extracted from experimental C-V data. The NC-GAA shows reduction in the off current by one order of magnitude and a 40% on-current boost. If the gate work function is shifted to align the NC-GAA's off-current with the IRDS high performance requirement, it is shown that NC-GAA can achieve the on-current and V DD requirement of every node through the "0.7 eq node," which is the last node predicted in the 2020 IRDS Table. Furthermore, NC-GAA can even achieve a "0.5 eq node," which is three additional nodes beyond the baseline "1.5 nm node." We also show that these benefits are retained over a varying set of ferroelectric parameters. [ABSTRACT FROM AUTHOR]

A new deep-learning-based parameter extraction for a global (multiple gate lengths) BSIM-CMG drain-current model is presented in this paper. The approach starts with generating 300K training dataset, consisting of 778 million data points to train the deep learning engine. Training data is generated by Monte Carlo simulation. The I-V data and the device geometry information from multiple devices serve to train a deep-learning (DL) model to predict BSIM-CMG parameters. The performance of DL-based extraction is verified by using the trained DL model to extract parameters of 10 nm FinFET technology simulated with TCAD. The DL-extracted BSIM-CMG model shows a good accuracy for eight different gate-lengths. The created BSIM-CMG global model was also able to reproduce the scalability in key electrical performance parameters such as off current I o f f , saturation current I s a t , linear current I l i n and the threshold voltage in linear V t h , l i n and saturation V t h , s a t conditions. The developed solution significantly reduces the model extraction time for a global BSIM-CMG model. This new technique can expedite the development of process design kits (PDK). • Automatic parameter extraction of BSIM-CMG I-V global parameters. • Tested on TCAD simulated data calibrated to Intel 10 nm node with gate lengths from 16 nm to 100 nm. • Created global model captures the trends in I-V data and key electrical parameters accurately. [ABSTRACT FROM AUTHOR]

Studies have shown that prebiotics can affect meat quality; however, the underlying mechanisms remain poorly understood. This study aimed to investigate whether prebiotics affect the flavor of chicken meat via the gut microbiome and metabolome. The gut content was collected from chickens fed with or without prebiotics (galacto-oligosaccharides or xylo-oligosaccharides) and subjected to microbiome and metabolome analyses, whereas transcriptome sequencing was performed using chicken breast. Prebiotic supplementation yielded a slight improvement that was not statistically significant in the growth and production performance of chickens. Moreover, treatment with prebiotics promoted fat synthesis and starch hydrolysis, thus increasing meat flavor by enhancing lipase and α-amylase activity in the blood of broiler chickens. The prebiotics altered the proportions of microbiota in the gut at different levels, especially microbiota in the phyla Bacteroidetes and Firmicutes, such as members of the Alistipe s, Bacteroides , and Faecalibacterium genera. Furthermore, the prebiotics altered the content of cecal metabolites related to flavor substances, including 8 types of lysophosphatidylcholine (lysoPC) and 4 types of amino acid. Differentially expressed genes (DEG s) induced by prebiotics were significantly involved in fatty acid accumulation processes, such as lipolysis in adipocytes and the adipocytokine signaling pathway. Changes in gut microbiota were correlated with metabolites, for example, Bacteroidetes and Firmicutes were positively and negatively correlated with lysoPC, respectively. Finally, DEGs interacted with cecal metabolites, especially meat-flavor-related amino acids and their derivatives. The findings of this study integrated and incorporated associations among the gut microbiota, metabolites, and transcriptome, which suggests that prebiotics affect the flavor of chicken meat. Chickens fed with the galacto-oligosaccharide or xylo-oligosaccharide prebiotics exhibited alterations in their growth and production performance, metabolites, microbiota, and transcriptome. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, flicker noise behavior of lateral non-uniformly doped MOSFET is studied using impedance field method. Our study shows that Klaassen Prins (KP) method, which forms the basis of noise model in MOSFETs, underestimates flicker noise in such devices. The same KP method overestimates thermal noise by 2–3 orders of magnitude in similar devices as demonstrated in Roy et al. (2007). This apparent discrepancy between thermal and flicker noise behavior lies in origin of these noises, which leads to opposite trend of local noise power spectral density vs doping. We have modeled the physics behind such behavior, which also explain the trends observed in the measurements (Agarwal et al., 2015). [ABSTRACT FROM AUTHOR]

In this work, we have modeled the impact of substrate depletion in fully-depleted silicon-on-insulator (FDSOI) transistor and have extensively verified the model for both NMOS and PMOS with geometrical and temperature scaling. The model has an accurate behavior for C – V and I – V characteristics and preserves the smooth behavior of the high order derivatives. Model validation is done at 50 nm technology node with state of the art FDSOI transistors provided by Low-power Electronics Association and Project (LEAP) and excellent agreement with the experimental data is achieved after parameter extraction. [ABSTRACT FROM AUTHOR]

Abstract: A turnkey, production circuit simulation ready compact model for cylindrical/surround gate transistors has been developed. The core of the model contains an enhanced surface potential based description of the charge in the channel. Analytical expressions for channel current and terminal charges have been derived. A method to account for quantum confinement in the cylindrical structure in a compact model framework is described. For the first time we present calibration results of such a model to a cylindrical gate technology that also exhibits asymmetric I–V characteristics. [Copyright &y& Elsevier]

Abstract: Planar band-to-band tunneling FETs (TFETs) have been fabricated on silicon-on-insulator (SOI) substrates using conventional CMOS technologies with a highly scaled sub-60nm gate length (effective gate length [L g]∼40nm due to an overlap between the source and gate) and different anneal sequences. The optimal anneal sequence including spike and flash annealing resulted in a drive ON current (I ON))>100μA/μm with I ON/IOFF >105 at a drain bias of −1V. The devices exhibited negative differential resistance and non-linear subthreshold temperature dependencies, consistent with the band-to-band tunneling mechanism. Simulations using a 2-D TCAD simulator, MEDICI, agreed with experimental data, demonstrating the possibility of Si tunnel transistors in logic applications. [Copyright &y& Elsevier]

Abstract: In this paper a computationally efficient surface-potential-based compact model for fully-depleted SOI MOSFETs with independently-controlled front- and back-gates is presented. A fully-depleted SOI MOSFET with a back-gate is essentially an independent double-gate device. To the best of our knowledge, existing surface-potential-based models for independent double-gate devices require numerical iteration to compute the surface potentials. This increases the model computational time and may cause convergence difficulties. In this work, a new approximation scheme is developed to compute the surface potentials and charge densities using explicit analytical equations. The approximation is shown to be computationally efficient and preserves important properties of fully-depleted SOI MOSFETs such as volume inversion. Drain current and charge expressions are derived without using the charge sheet approximation and agree well with TCAD simulations. Non-ideal effects are added to describe the I–V and C–V of a real device. Source-drain symmetry is preserved for both the current and the charge models. The full model is implemented in Verilog-A and its convergence is demonstrated through transient simulation of a coupled ring oscillator circuit with 2020 transistors. [Copyright &y& Elsevier]

Abstract: Aggressive scaling of the gate-oxide thickness has made gate-tunneling current an essential aspect of MOSFET modeling and this leakage current density continues to increase for every process generation. Accurate compact models for gate-tunneling current and its source/drain partition are extremely critical to valid circuit performance in the 90nm technology or beyond. Gate current partition has been studied by several authors [Cao K, et al. “BSIM4 gate leakage model including source–drain partition,” in IEDM Tech. Dig., San Francisco, CA, Dec. 2000. p. 815–8; R. van Langevelde et al., Gate current: modeling, ΔL extraction and impact on RF performance, in IEDM Tech. Dig., Washington, DC, Dec. 2001. p. 289–92; Shih W-K, et al., “A general partition scheme for gate leakage current suitable for MOSFET compact models,” in IEDM Tech. Dig., Washington DC., Dec. 2001. p. 293–6]. In this paper, an insight on the common/difference of these different gate leakage current partition schemes into source/drain has been provided and the accuracy of BSIM4 [Cao K, et al. “BSIM4 gate leakage model including source–drain partition,” in IEDM Tech. Dig., San Francisco, CA, Dec. 2000. p. 815–8] partition scheme is confirmed with comparing to the new derived equation, which incorporates the gate current into the inhomogeneous term calculation. [Copyright &y& Elsevier]

This paper describes a unified framework to model the floating-body effects of various SOI MOSFET operation modes, including body-contacted mode, partially depleted mode and fully depleted mode. As the operation mode is dimension and bias dependent, different modes can co-exist in a single SOI technology. A smooth transit from one type of operation mode to another is thus essential and has been included in the model. In addition, the floating-body effects can couple to a number of other SOI specific phenomena such as heating assisted impact ionization, gate tunneling induced dynamic behavior, and operation mode dependent small signal output resistance. A methodology to model the overall SOI MOSFET behavior due to the combination of multiple floating-body related effects will also be described. [Copyright &y& Elsevier]

This paper attempts to provide a general overview and guideline to develop a practical model for CMOS devices in the sub-0.1μm generations. It starts by giving an overview of the different modeling options including the charge-based approach, the surface potential based approach, and the conductance-based approach. Their relative advantages and weaknesses will be discussed. The evolution of the BSIM models from its first generation to the most recent release will be used as an example for the development of a practical device model. It will be followed by a discussion on how the accelerated technology development may impact the traditional modeling methodologies. A new paradigm to incorporate modern software engineering methodology to shorten model development cycle will be presented. [Copyright &y& Elsevier]

Normalized mutual integral difference operator (NMIDO), a novel experimental method for extracting the threshold voltage of MOSFETs, is presented in this paper. The basic principle of this method is to use the extreme spectrum characteristics of the NMIDO to find the threshold voltage. We have demonstrated numerically that this method is applied in the extraction of the threshold voltage of MOSFETs with different effective channel length and different parasitic series resistance cases. It has been shown that this method is sensitive to the channel length variation while insensitive to the parasitic resistance component. The extracted results on the threshold voltage of MOSFETs have also been compared with those obtained by the second-derivative method and the good agreement has been found, showing the advantage of the method presented here. [Copyright &y& Elsevier]

The adaptation to hypoxia in high altitude areas has great research value in the field of biological sciences. Tibetan chicken has unique adaptability to high-altitude, low pressure and anoxic conditions, and served as a biological model to search for genetic diversity of hypoxia adaption. The whole genome re-sequencing technology was conducted to investigate the genetic diversity. In this study, we obtained quantity genetic resource, contained 5164926 single nucleotide polymorphisms (SNPs), 237504 Insertion/Deletion (InDel), 55606 structural variation types in all chromosomes of Tibetan chicken. Moreover, 17154 non-synonymous mutations, 45763 synonymous mutations, 258 InDel mutations and 9468 structural mutations were detected in coding sequencing (CDS) region. Furthermore, SNPs occur in 591 genes, including HIF1A, VEGF, MAPK 8/9/10/11, PPARA/D/G, NOTCH2, and ABCs, which were involved in 14 hypoxia-related pathways, such as VEGF signaling pathway, MAPK signaling pathway, PPAR signaling pathway and Notch signaling pathway. Among them, 19 genes with non-synonymous SNP variation in CDS were identified. Moreover, structure variation in CDS also occurred in the mentioned above genes with SNPs. This study provides useful targets for clarifying the hypoxia adaptability of the domestication of chickens in Tibetan and may help breeding efforts to develop improved breeds for the highlands. [ABSTRACT FROM AUTHOR]

As a ubiquitous heavy metal, cadmium (Cd) is highly toxic to various organs. However, the effects and molecular mechanism of Cd toxicity in the chicken heart remain largely unknown. The goal of our study was to investigate the cardiac injury in chickens' exposure to Cd. We detected the levels of oxidative stress–related molecules in the Cd-induced chicken heart, and assessed the histopathological changes by hematoxylin and eosin staining. RNA sequencing was performed to identify differentially expressed mRNAs between the Cd-induced group and control group. The expression of candidate genes involved in oxidative stress was certified by quantitative reverse transcription PCR. Our results showed that the expression of glutathione, peroxidase, and superoxide dismutase was significantly decreased and malondialdehyde was increased in the heart of chickens by Cd induction. The disorderly arranged cardiomyocytes, swelled and enlarged cells, partial cardiomyocyte necrosis, blurred morphological structure, and notable inflammatory cell infiltration were observed in the Cd-induced chicken heart. RNA sequencing identified 23 upregulated and 11 downregulated mRNAs in the heart tissues of the chicken in the Cd-induced group, and functional pathways indicated that they were associated with oxidative stress. Moreover, CREM, DUSP8, and ITGA11 expressions were significantly reduced, whereas LAMA1 expression was induced in heart tissue of chickens by Cd treatment. Overall, our findings revealed that oxidative stress and pathological changes in the chicken heart could be triggered by Cd. The mRNA transcriptional profiles identified differentially expressed genes in the chicken heart by Cd induction, revealing oxidative stress–related key genes and enhancing our understanding of Cd toxicity in the chicken heart. [ABSTRACT FROM AUTHOR]

• We demonstrate the importance of considering the influence of oxygen vacancy in ferroelectric capacitors. • In-situ synchrotron X-ray techniques were used to examine the polarization wake-up effect of HZO. • Oxygen vacancy creates a trade-off between polarization wake-up enhancement and interfacial trap states. TiN/Hf 0.5 Zr 0.5 O 2 (HZO) is a popular heterostructure for HZO-based ferroelectric devices. In this study, in-situ synchrotron X-ray techniques were used to examine the ferroelectric wake-up effect of HZO in relation to TiN electrodes. TiN was shown to favor orthorhombic (O)/ferroelectric phase of HZO, while promoting the reconstruction of the TiN/HZO interface through the formation of oxygen vacancy (V O ′ ′) states. Real-time changes in polarization under an applied voltage (electrical stress) indicated that V O ′ ′ regulates the observed ferroelectric wake-up effects. The changes observed using in-situ X-ray analysis included an intensification of the V O ′ ′ signal and the breaking of Hf-O bonds under electrical stress over a period of 1000 s. Stress-driven V O ′ ′ increased polarization without degrading the interface, as indicated by the capacitance–voltage (C-V) characteristics of the device. It appears that V O ′ ′ woke up HZO polarization without introducing any structural transitions. Despite the fact that V O ′ ′ formed concomitantly with the O -phase following TiN capping, it appears that V O ′ ′ plays an independent role in regulating polarization under an applied electrical field. Thus, V O ′ ′ creates a trade-off between polarization wake-up enhancement and trap states. Furthermore, the results of cyclic polarization-voltage (P-V) measurement show that stress-induced V O ′ ′ near the TiN/HZO interface is conducive to enhancing the ferroelectricity with fewer wake-up operation cycles. [ABSTRACT FROM AUTHOR]