This article introduces a novel 20 V radiation-hardened high-voltage metal-oxide-semiconductor field-effect transistor(MOSFET)driver with an optimized input circuit and a drain-surrounding-source(DSS)structure.The inp...This article introduces a novel 20 V radiation-hardened high-voltage metal-oxide-semiconductor field-effect transistor(MOSFET)driver with an optimized input circuit and a drain-surrounding-source(DSS)structure.The input circuit of a conventional inverter consists of a thick-gate-oxide n-type MOSFET(NMOS).These conventional drivers can tolerate a total ionizing dose(TID)of up to 100 krad(Si).In contrast,the proposed comparator input circuit uses both a thick-gate-oxide p-type MOSFET(PMOS)and thin-gate-oxide NMOS to offer a high input voltage and higher TID tolerance.Because the thick-gate-oxide PMOS and thin-gate-oxide NMOS collectively provide better TID tolerance than the thick-gate-oxide NMOS,the circuit exhibits enhanced TID tolerance of>300 krad(Si).Simulations and experimental date indicate that the DSS structure reduces the probability of unwanted parasitic bipolar junction transistor activation,yielding a better single-event effect tolerance of over 81.8 MeVcm^(2)mg^(-1).The innovative strategy proposed in this study involves circuit and layout design optimization,and does not require any specialized process flow.Hence,the proposed circuit can be manufactured using common commercial 0.35μm BCD processes.展开更多
This paper presents a fully-differential CMOS dynamic comparator for use in high-speed pipelined ADCs with low stage resolution. Because the architecture is based on the coupled current sources and differential input ...This paper presents a fully-differential CMOS dynamic comparator for use in high-speed pipelined ADCs with low stage resolution. Because the architecture is based on the coupled current sources and differential input pairs, this comparator＇s threshold voltage can be adjusted to a desired level. Compared with traditional comparators, this one shows significant improvement in area,power,and speed. Fabricated in 0.35μm CMOS technology,it occupies only 30μm × 70μm. Simulation and measurement results indicate the comparator has a sampling frequency up to 1GHz with 2Vpp differential input signal range and only 181μW power consumption under a 3.3V supply. The speed/power ratio reaches up to 5524GS/J.展开更多
The demand of present technology inviting the popularity of multivalued optical computation system to coup up with the latest scenario of ultrahigh processing speed and handling large amount of data The magnitude comp...The demand of present technology inviting the popularity of multivalued optical computation system to coup up with the latest scenario of ultrahigh processing speed and handling large amount of data The magnitude comparator is the heart of the arithmetic and logic unit(ALU)in any logical processing and computing system.In this paper,a trinary magnitude comparator circuit has been proposed and implemented with modified trinary number(MTN)system.Optical tree architecture(OTA)of the proposed circuit has been realized reasonably using Savart plate and spatial light modulators(SLM).A simulation algorithm has also been developed and implemented to prove the authenticity of the proposed circuit through the simulation.展开更多
This paper presents an energy efficient successive-approximation register(SAR)analog-to-digital converter(ADC)for low-power applications.To improve the overall energy-efficiency,a skipping-window technique is used to ...This paper presents an energy efficient successive-approximation register(SAR)analog-to-digital converter(ADC)for low-power applications.To improve the overall energy-efficiency,a skipping-window technique is used to bypass corresponding conversion steps when the input falls in a window indicated by a time-domain comparator,which can provide not only the polarity of the input,but also the amount information of the input.The timedomain comparator,which is based on the edge pursing principle,consists of delay cells,two NAND gates,two D-flip-flop register-based phase detectors and a counter.The digital characteristic of the comparator makes the design more flexible,and the comparator can achieve noise and power optimization automatically by simply adjusting the delay cell number.An energy efficient digital-to-analog converter(DAC)control scheme suitable for the skipping window technique is also developed to reduce the switching energy during SAR conversion.Together with the skipping-window technique,the linearity and the power consumption of the SAR ADC are improved.The impact of different window sizes on comparison cycles,DAC switching energy and the overall energy efficiency is analyzed.Simulation results show that the proposed skipping-window technique can improve the overall energy-efficiency of the SAR ADC,as well as the linearity,and the optimized window size for the overall energy efficiency will vary with the DAC switching energy.展开更多
The design of a new type of latching voltage comparator ZJ03 is described.Thecommon voltage comparators consist of multistage DC amplifiers,for which it is difficult to realizehigh speed and high precision.The ZJ03 co...The design of a new type of latching voltage comparator ZJ03 is described.Thecommon voltage comparators consist of multistage DC amplifiers,for which it is difficult to realizehigh speed and high precision.The ZJ03 comparator contains a controlled positive feedbackamplifier.Therefore,it is capable of realizing high speed and high precision.For improving theperformance and producibility,the tolerance extension,design centering and potential adaptingtechniques are used in the design of comparator ZJ03.展开更多
The effects of stage numbers on power dissipation of pipeline analog-to-digital converter （ADC） are studied and a novel design method aiming for power optimization is presented. In this method, a minimum comparator ...The effects of stage numbers on power dissipation of pipeline analog-to-digital converter （ADC） are studied and a novel design method aiming for power optimization is presented. In this method, a minimum comparator number algorithm （MCNA） is first introduced, and then the optimum distribution of resolutions through pipeline ADC stages is deduced by MCNA. Based on the optimum stage-resolution distribution, an optimization method is established, which examines the precise function between ADC power and stage resolutions with a parameter of power ratio （Rp）. For 10-bit pipeline ADC with scaling down technology, the simulation results by using MATLAB CAD tools show that an eight-stage topology with 1-bit RSD correction achieves the power optimization indicated by the power reduction ratio.展开更多
A novel design of multiplex differential voltage comparators(MDVC) is presented for reducing current and power dissipation. According to the special properties of relational operation and logical operation, parts of t...A novel design of multiplex differential voltage comparators(MDVC) is presented for reducing current and power dissipation. According to the special properties of relational operation and logical operation, parts of the comparators are redundant in some instances, and thus can be turned off. By selecting and switching the current routes, several effective differential pairs are biased by a single tail current stage-by-stage and the redundant comparators are turned off by cutting their tail currents. As a result, the quiescent current and power consumption are greatly decreased. The switching of current is achieved by the input differential pair transistors themselves and hence no extra switches are required. When a MDVC is used in a flash analog-to-digital converter(ADC), its current dissipation is much lower than that of the conventional comparators. This architecture can also be used in window-comparators, maximum or minimum comparators, and comparators for logical operations. The power dissipation in all these cases could be reduced significantly.展开更多
A low-voltage, high-speed flash ADC is designed. The bottleneck of the operation speed in the low-voltage region is the delay time increase of the comparator. The temporarily boosted comparator is proposed to address ...A low-voltage, high-speed flash ADC is designed. The bottleneck of the operation speed in the low-voltage region is the delay time increase of the comparator. The temporarily boosted comparator is proposed to address this problem. The proposed circuit only boosts the supply voltage in the comparison phase, and therefore, can reduce the delay time while keeping the power overhead to a minimum. Moreover, the body bias control calibration is combined with the temporarily boosted technique. This helps to create a low-power and high-precision comparator. A 0.5-V, 6-bit flash ADC was designed by using 65-nm CMOS technology to demonstrate the effectiveness of the proposed technique. The simulation results showed a high sampling frequency of 1.2 GHz, a low power consumption of 1.4 mW, and an FOM of 28 fJ/conv.-step even at a low supply voltage of 0.5 V.展开更多
This paper presents a two-dimension time-domain comparator suitable for low power successive-approximation register(SAR)analog-to-digital converters(ADCs).The proposed two-dimension time-domain comparator consists of ...This paper presents a two-dimension time-domain comparator suitable for low power successive-approximation register(SAR)analog-to-digital converters(ADCs).The proposed two-dimension time-domain comparator consists of a ring oscillator collapse-based comparator and a counter.The propagation delay of a voltage controlled ring oscillator depends on the input.Thus,the comparator can automatically change the comparison time according to its input difference,which can adjust the power consumption of the comparator dynamically without any control logic.And a counter is utilized to count the cycle needed to finish a comparison when the input difference is small.Thus,the proposed comparator can not only provide the polarity of the input,but also the amount information of the input,which helps to skip most of the SAR cycles when the initial input is small.Thus,most energy can be saved when the initial input is small.The proposed time-domain comparator is designed in 0.18μm CMOS technology.Simulation results demonstrate that the comparator can not only save power consumption,but also give the design flexibility,and the current is only nA level when the supply voltage is 0.6 V.展开更多
In recent studies, reversible logic has emerged as a great scene of research, having applications in low power CMOS circuits, optical computing, quantum computing and nanotechnology. The classical logic gates such as ...In recent studies, reversible logic has emerged as a great scene of research, having applications in low power CMOS circuits, optical computing, quantum computing and nanotechnology. The classical logic gates such as AND, OR, EXOR and EXNOR are not reversible. In the existing literature, reversible sequential circuits designs are offered that are improved for the number of the garbage outputs and reversible gates. Minimizing the number of garbage is very noticeable. In the present paper, we show a design of the reversible comparator based on the quantum gates implementation of the reversible DG gate. The reversible DG gate is designed by using 3 × 3 quantum gates such as NOT, CNOT, Controlled-V and Controlled-V+ gates. Also, we have used the TR gate and various types of quantum gates in the implementation results. Low power three-bit comparator is designed using DG Gate, New Gate and Fredkin Gate. In order to evaluate the benefit of using the DG gate proposed in this paper, one-bit comparator is constructed. The design is useful for the future computing techniques like quantum computers. The proposed designs are implemented using VHDL and functionally investigated using Quartus II simulator.展开更多
To fill the continuous needs for faster processing elements with less power consumption causes large pressure on the complementary metal oxide semiconductor(CMOS)technology developers.The scaling scenario is not an op...To fill the continuous needs for faster processing elements with less power consumption causes large pressure on the complementary metal oxide semiconductor(CMOS)technology developers.The scaling scenario is not an option nowadays and other technologies need to be investigated.The quantum-dot cellular automata(QCA)technology is one of the important emerging nanotechnologies that have attracted much researchers’attention in recent years.This technology has many interesting features,such as high speed,low power consumption,and small size.These features make it an appropriate alternative to the CMOS technique.This paper suggests three novel structures of XNOR gates in the QCA technology.The presented structures do not follow the conventional approaches to the logic gates design but depend on the inherent capabilities of the new technology.The proposed structures are used as the main building blocks for a single-bit comparator.The resulted circuits are simulated for the verification purpose and then compared with existing counterparts in the literature.The comparison results are encouraging to append the proposed structures to the library of QCA gates.展开更多
It is vital segment to choose the right comparator product during the development and study of generic medicinal product, and this is also definitely specified in the relevant documents from the China Food and Drug Ad...It is vital segment to choose the right comparator product during the development and study of generic medicinal product, and this is also definitely specified in the relevant documents from the China Food and Drug Administration (CFDA)that the comparator product should be innovator product or internationally recognized same medicinal product,which is used in the re-evaluation of generic medicinal product or marketed authorization application of the generic medicinal product.To facilitate the domestic and foreign pharmaceutical enterprises to choose and determine comparator product,four medicinal product evaluation procedures,as well as the corresponding marketed medicinal product list,are detailed elaborated in this paper.At the same time, by taking the Mifepristone Tablet (200mg)as example,the search and determination process of the comparator product for generic medicinal product application in the EU is illustrated with the combination of different marketed medicinal product lists.展开更多
There are magnetic interference problems in the applications of DC current comparator. Analysis on the magnetic effectiveness which is applied by the external magnetic field is introduced in this paper. The effectiven...There are magnetic interference problems in the applications of DC current comparator. Analysis on the magnetic effectiveness which is applied by the external magnetic field is introduced in this paper. The effectiveness is proved by the actual results which are compared with the magnetic- circuit method and the finite element method. In addition, the reference comment is given which can be used in the practical work of DC current comparator shield design.展开更多
Objective: We aim to analyze the surgical nursery of abdominal wall hernias in adults between two poorly fitted medical environments, the Regional Hospital Center of Tsévié (RHC-T) and the Prefectural Hospit...Objective: We aim to analyze the surgical nursery of abdominal wall hernias in adults between two poorly fitted medical environments, the Regional Hospital Center of Tsévié (RHC-T) and the Prefectural Hospital Center of Kpalimé (PHC-K) in Togo. Methodology: It was a retrospective, descriptive and comparative study carried out over five years (2018-2022) focusing on abdominal wall hernias in adults. Information was gathered from the patients’clinical notes and registers on the frequency of hernias, the anatomo-clinical forms of hernias, the type of anesthesia, the hernia repair technique and the postoperative evolution. Results: Of the 1022 and 1026 operations performed, 312 and 412 were hernial repairs, representing 30.5% and 41.2% of operations at RHC-T and PHC-K respectively (p = 0.001). The inguinal hernia was the most often found in 83.7% (n = 261) at RHC-T versus 76.6% (n = 324) at PHC-K. Herniorrhaphy was the most frequently used repair method, in 93.6% (n = 292) of patients at RHC-T and in 91.3% (n = 376) at PHC-K (p = 0.11). Postoperative complications were noted in 5.1% of cases (n = 16) at RHC-T versus 3.5% of cases (n = 15) at PHC-K (p = 0.307). These complications included scrotal hematomas, surgical areas infections, and orchitis. We recorded 1.3% (n = 4) and 0.8% (n = 3) deaths at RHC-T and PHC-K respectively (p = 0.496). Conclusion: There is homogeneity in the treatment of hernia in these two hospitals in Togo.展开更多
The plastid genome(plastome)represents an indispensable molecular resource for studying plant phylogeny and evolution.Although plastome size is much smaller than that of nuclear genomes,accurately and efficientlyannot...The plastid genome(plastome)represents an indispensable molecular resource for studying plant phylogeny and evolution.Although plastome size is much smaller than that of nuclear genomes,accurately and efficientlyannotating and utilizing plastome sequences remain challenging.Therefore,a streamlined phylogenomic pipeline spanning plastome annotation,phylogenetic reconstruction and comparative genomics would greatly facilitate research utilizing this important organellar genome.Here,we develop PlastidHub,a novel web application employing innovative tools to analyze plastome sequences.In comparison with existing tools,key novel functionalities in PlastidHub include:(1)standardization of quadripartite structure;(2)improvement of annotation flexibility and consistency;(3)quantitative assessment of annotation completeness;(4)diverse extraction modes for canonical and specialized sequences;(5)intelligent screening of molecular markers for biodiversity studies;(6)genelevel visual comparison of structural variations and annotation completeness.PlastidHub features cloud-based web applications that do not require users to install,update,or maintain tools;detailed help documents including user guides,test examples,a static pop-up prompt box,and dynamic pop-up warning prompts when entering unreasonable parameter values;batch processing capabilities for all tools;intermediate results for secondary use;and easy-to-operate task flows between fileupload and download.A key feature of PlastidHub is its interrelated task-based user interface design.Give that PlastidHub is easy to use without specialized computational skills or resources,this new platform should be widely used among botanists and evolutionary biologists,improving and expediting research employing the plastome.PlastidHub is available at https://www.plastidhub.cn.展开更多
The oscillating hydrofoil represents a promising technology for harvesting energy from tidal currents.While previous research has primarily focused on oscillating hydrofoils utilizing a fully activated control strateg...The oscillating hydrofoil represents a promising technology for harvesting energy from tidal currents.While previous research has primarily focused on oscillating hydrofoils utilizing a fully activated control strategy,the industry predominantly employs a semi-activated control strategy in existing tidal current energy converters.It is essential to identify the differences in predicted energy-harvesting performance between these two controlling strategies through experimental modeling or numerical studies.Furthermore,the suitability of the fully activated control strategy in predicting the energy-harvesting capabilities of oscillating hydrofoils is evaluated.The 2D numerical models of hydrofoil based on fully activated and semi-activated control strategies have been developed and validated.The amplitudes of heaving and pitching movements for the fully activated hydrofoil are determined to match those of the semi-activated hydrofoil.The results show that the main difference between the two control strategies lies in the phase shift occurring between the pitching and heaving motions.This phase shift affects the lift force and its coordination with the heaving velocity,which in turn affects the power output.Notably,the maximum relative efficiency difference obtained between the fully activated and semi-activated control strategies can reach 191%.展开更多
Bathymodiolus mussels distribute in both deep-sea cold seep and hydrothermal vent environments,whose endosymbiotic gill tissue is a prominent character for the adaptation of extreme habitats.However,few studies explor...Bathymodiolus mussels distribute in both deep-sea cold seep and hydrothermal vent environments,whose endosymbiotic gill tissue is a prominent character for the adaptation of extreme habitats.However,few studies explored the adaptation mechanisms through comparative transcriptome sequencing and analysis of different tissues between seep mussels and vent mussels.We performed the comparative transcriptome sequencing and analysis for three tissue types(gill,mantle,and adductor muscle)of Bathymodiolus mussels collected from a cold seeping site Station S 11 and the 50-km away hydrothermal field Minami-Ensei Knoll in the Okinawa Trough.Results show that gene expression patterns had distinct tissue specificity.Compared with the non-endosymbiotic tissues(mantle and adductor muscle),the significantly strengthened gene functions in endosymbiotic gill included microbial recognition(fibrinogen C domain-containing protein 1-B-like(fibcd),fibrinogen-related protein 8(frp),peptidoglycan recognition proteins(pgrp),and C-type lectin(clec)),cell apoptosis and immunity(interferon regulatory factor 1/2-like 1(ir f),cathepsin D(ctsd),caspase 2(casp 2)),and antioxidant capacity(copper/zinc superoxide dismutase(czsod),glutathione peroxidase(gpx),selenoprotein(sel)),in both seep and vent individuals.Consistent with metal accumulation,high expression levels of genes related to heavy metal detoxification(cytochrome P 450(cyp),ferritin-like(ftl),metallothionein(mt),glutathione S-transferase(gst))were also observed in gill.Moreover,to adapt to high hydrostatic pressure in the deep sea,the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways associated with cellular community were significantly enriched in all three tissues,suggesting the regulation of cell structure and cell adhesion at transcriptional level.This study obtained gene expression profiles of deep-sea mussels subsisting at cold seep and hydrothermal vent sites,which could lay foundations for comprehensive investigations of molecular basis in adaptation of deep-sea mussels to the two extreme ecosystems.展开更多
Lactococcus lactis,a major starter culture in the dairy industry,has been widely applied in food fermentation.While current research has primarily focused on evaluating its role during fermentation,genomic investigati...Lactococcus lactis,a major starter culture in the dairy industry,has been widely applied in food fermentation.While current research has primarily focused on evaluating its role during fermentation,genomic investigations into its genetic diversity and functional adaptability remain limited.In this study,199 L.lactis strains isolated from Chinese traditional artisanal cheeses(72 bovine,71 goat,and 56 yak milk cheese isolates)were subjected to comparative genomic analysis.Genomic characteristic analysis indicated that bovine milk strains possess larger genomes and the highest number of unique genes.Functional characterization further demonstrated notable differences in carbohydrate metabolism among strains from different sources,with yak milk strains enriched in enzymes involved in complex polysaccharide degradation,including members of the carbohydrate esterases family.Moreover,strains from different sources exhibit distinct strategies for lactose hydrolysis and metabolic utilization,reflecting adaptive evolution to their specific nutritional niches.Analysis of the antibiotic resistance profile suggests that L.lactis predominantly harbors glycopeptide and lincosamide resistance genes,encompassing four distinct resistance mechanisms.Collectively,this study reveals the genetic diversity and adaptive evolution of L.lactis strains from different sources and identifies key genes associated with carbohydrate degradation,lactose metabolism,and antibiotic resistance,providing concrete genetic evidence for the selection of efficient and safe industrial fermentation strains.展开更多
Although previous studies have analyzed the unique structural characteristics of the polar vortices on Earth,Venus,Mars,and Titan,the understanding of the polar vortices on Venus and Titan is primarily based on small-...Although previous studies have analyzed the unique structural characteristics of the polar vortices on Earth,Venus,Mars,and Titan,the understanding of the polar vortices on Venus and Titan is primarily based on small-scale case studies due to the limited resolution and coverage of observational data.Conducting a detailed comparison of the polar vortex characteristics between the major terrestrial planets and Titan in the solar system is more challenging.In order to more finely compare the polar vortex characteristics of the main terrestrial planets in the solar system with Titan,we have achieved the optimal estimation of the polar vortices of Venus and Titan under existing conditions based on the advanced VCD2.3 and TitanWRF model.At the same time,combining ERA5 and EMARS databases,a detailed spatiotemporal comparison of polar vortex characteristics between terrestrial planets with atmospheres in the solar system and the most Earth-like Titan satellite was conducted for the first time.Here,we demonstrate that:(1)The circulation characteristics of Mars above the 1 mbar level are very similar to those at 1000 mbar in the lower layers of Titan,with seasonal variations of the same height.(2)In contrast to the vortex structure that is stably maintained in the lead direction in the polar regions of Mars and Earth during the winter,the time of occurrence of the peak vortex intensity at Titan and Venus is gradually shifted forward with increasing altitude.(3)When Venus undergoes vortex instability drift,the polar vortex at an altitude of 1 mbar breaks up into banded structures,a phenomenon that closely resembles the twisting deformation of PV structures during weak stratospheric polar vortex events on Earth.展开更多
This paper conducts clustering,potential semantic indexing,comparison,and inductive analysis of research papers on marketing between China and the UK from January 2020 to September 2024.The study found that the Chines...This paper conducts clustering,potential semantic indexing,comparison,and inductive analysis of research papers on marketing between China and the UK from January 2020 to September 2024.The study found that the Chinese marketing research focuses on digital transformation,policy impact,value co-creation,and emerging e-commerce models.In contrast,the UK marketing research focuses more on sustainability,technology integration,real-time research,and personalized marketing strategies.The study also found that there were few marketing articles published in Chinese and CSSCI journals in China,while the SSCI journals published in English were 62 times more than in Chinese.According to the research,digital marketing and data-driven decision-making,diversified marketing channels,sustainability and circular economy,technological innovation and cutting-edge technology application,meta-universe and blockchain technology,AI+marketing development,brand building,and international market expansion will become the research hotspots in the field of marketing in the future.The research suggests that China should strengthen the construction of an academic marketing platform,and China and the UK should strengthen cooperation in marketing research,learn from each other's strengths,and jointly give full play to their advantages in technology application,market and economy,strategy and innovation,and social media,to contribute to global economic development and marketing research.展开更多
基金supported by the National Natural Science Foundation of China(U2241221).
文摘This article introduces a novel 20 V radiation-hardened high-voltage metal-oxide-semiconductor field-effect transistor(MOSFET)driver with an optimized input circuit and a drain-surrounding-source(DSS)structure.The input circuit of a conventional inverter consists of a thick-gate-oxide n-type MOSFET(NMOS).These conventional drivers can tolerate a total ionizing dose(TID)of up to 100 krad(Si).In contrast,the proposed comparator input circuit uses both a thick-gate-oxide p-type MOSFET(PMOS)and thin-gate-oxide NMOS to offer a high input voltage and higher TID tolerance.Because the thick-gate-oxide PMOS and thin-gate-oxide NMOS collectively provide better TID tolerance than the thick-gate-oxide NMOS,the circuit exhibits enhanced TID tolerance of>300 krad(Si).Simulations and experimental date indicate that the DSS structure reduces the probability of unwanted parasitic bipolar junction transistor activation,yielding a better single-event effect tolerance of over 81.8 MeVcm^(2)mg^(-1).The innovative strategy proposed in this study involves circuit and layout design optimization,and does not require any specialized process flow.Hence,the proposed circuit can be manufactured using common commercial 0.35μm BCD processes.
文摘This paper presents a fully-differential CMOS dynamic comparator for use in high-speed pipelined ADCs with low stage resolution. Because the architecture is based on the coupled current sources and differential input pairs, this comparator＇s threshold voltage can be adjusted to a desired level. Compared with traditional comparators, this one shows significant improvement in area,power,and speed. Fabricated in 0.35μm CMOS technology,it occupies only 30μm × 70μm. Simulation and measurement results indicate the comparator has a sampling frequency up to 1GHz with 2Vpp differential input signal range and only 181μW power consumption under a 3.3V supply. The speed/power ratio reaches up to 5524GS/J.
文摘The demand of present technology inviting the popularity of multivalued optical computation system to coup up with the latest scenario of ultrahigh processing speed and handling large amount of data The magnitude comparator is the heart of the arithmetic and logic unit(ALU)in any logical processing and computing system.In this paper,a trinary magnitude comparator circuit has been proposed and implemented with modified trinary number(MTN)system.Optical tree architecture(OTA)of the proposed circuit has been realized reasonably using Savart plate and spatial light modulators(SLM).A simulation algorithm has also been developed and implemented to prove the authenticity of the proposed circuit through the simulation.
基金This work was supported partly by the National Natural Science Foundation of China under Grant No.61704015the General program of Chongqing Natural Science Foundation(a special program for the fundamental and frontier research)under Grant No.cstc2019jcyj-msxmX0108.
文摘This paper presents an energy efficient successive-approximation register(SAR)analog-to-digital converter(ADC)for low-power applications.To improve the overall energy-efficiency,a skipping-window technique is used to bypass corresponding conversion steps when the input falls in a window indicated by a time-domain comparator,which can provide not only the polarity of the input,but also the amount information of the input.The timedomain comparator,which is based on the edge pursing principle,consists of delay cells,two NAND gates,two D-flip-flop register-based phase detectors and a counter.The digital characteristic of the comparator makes the design more flexible,and the comparator can achieve noise and power optimization automatically by simply adjusting the delay cell number.An energy efficient digital-to-analog converter(DAC)control scheme suitable for the skipping window technique is also developed to reduce the switching energy during SAR conversion.Together with the skipping-window technique,the linearity and the power consumption of the SAR ADC are improved.The impact of different window sizes on comparison cycles,DAC switching energy and the overall energy efficiency is analyzed.Simulation results show that the proposed skipping-window technique can improve the overall energy-efficiency of the SAR ADC,as well as the linearity,and the optimized window size for the overall energy efficiency will vary with the DAC switching energy.
文摘The design of a new type of latching voltage comparator ZJ03 is described.Thecommon voltage comparators consist of multistage DC amplifiers,for which it is difficult to realizehigh speed and high precision.The ZJ03 comparator contains a controlled positive feedbackamplifier.Therefore,it is capable of realizing high speed and high precision.For improving theperformance and producibility,the tolerance extension,design centering and potential adaptingtechniques are used in the design of comparator ZJ03.
基金Supported by the National Natural Science Foundation of China (No. 60072004)
文摘The effects of stage numbers on power dissipation of pipeline analog-to-digital converter （ADC） are studied and a novel design method aiming for power optimization is presented. In this method, a minimum comparator number algorithm （MCNA） is first introduced, and then the optimum distribution of resolutions through pipeline ADC stages is deduced by MCNA. Based on the optimum stage-resolution distribution, an optimization method is established, which examines the precise function between ADC power and stage resolutions with a parameter of power ratio （Rp）. For 10-bit pipeline ADC with scaling down technology, the simulation results by using MATLAB CAD tools show that an eight-stage topology with 1-bit RSD correction achieves the power optimization indicated by the power reduction ratio.
基金National Natural Science Foundation of China(60172004)PhD Subject Research Foundation of Ministry of Education of China(20010701003)
文摘A novel design of multiplex differential voltage comparators(MDVC) is presented for reducing current and power dissipation. According to the special properties of relational operation and logical operation, parts of the comparators are redundant in some instances, and thus can be turned off. By selecting and switching the current routes, several effective differential pairs are biased by a single tail current stage-by-stage and the redundant comparators are turned off by cutting their tail currents. As a result, the quiescent current and power consumption are greatly decreased. The switching of current is achieved by the input differential pair transistors themselves and hence no extra switches are required. When a MDVC is used in a flash analog-to-digital converter(ADC), its current dissipation is much lower than that of the conventional comparators. This architecture can also be used in window-comparators, maximum or minimum comparators, and comparators for logical operations. The power dissipation in all these cases could be reduced significantly.
文摘A low-voltage, high-speed flash ADC is designed. The bottleneck of the operation speed in the low-voltage region is the delay time increase of the comparator. The temporarily boosted comparator is proposed to address this problem. The proposed circuit only boosts the supply voltage in the comparison phase, and therefore, can reduce the delay time while keeping the power overhead to a minimum. Moreover, the body bias control calibration is combined with the temporarily boosted technique. This helps to create a low-power and high-precision comparator. A 0.5-V, 6-bit flash ADC was designed by using 65-nm CMOS technology to demonstrate the effectiveness of the proposed technique. The simulation results showed a high sampling frequency of 1.2 GHz, a low power consumption of 1.4 mW, and an FOM of 28 fJ/conv.-step even at a low supply voltage of 0.5 V.
基金This work was supported partly by the National Natural Science Foundation of China under grant No.61704015the General program of Chongqing Natural Science Foundation(a special program for the fundamental and frontier research)under grant No.cstc2019jcyj-msxmX0108.
文摘This paper presents a two-dimension time-domain comparator suitable for low power successive-approximation register(SAR)analog-to-digital converters(ADCs).The proposed two-dimension time-domain comparator consists of a ring oscillator collapse-based comparator and a counter.The propagation delay of a voltage controlled ring oscillator depends on the input.Thus,the comparator can automatically change the comparison time according to its input difference,which can adjust the power consumption of the comparator dynamically without any control logic.And a counter is utilized to count the cycle needed to finish a comparison when the input difference is small.Thus,the proposed comparator can not only provide the polarity of the input,but also the amount information of the input,which helps to skip most of the SAR cycles when the initial input is small.Thus,most energy can be saved when the initial input is small.The proposed time-domain comparator is designed in 0.18μm CMOS technology.Simulation results demonstrate that the comparator can not only save power consumption,but also give the design flexibility,and the current is only nA level when the supply voltage is 0.6 V.
文摘In recent studies, reversible logic has emerged as a great scene of research, having applications in low power CMOS circuits, optical computing, quantum computing and nanotechnology. The classical logic gates such as AND, OR, EXOR and EXNOR are not reversible. In the existing literature, reversible sequential circuits designs are offered that are improved for the number of the garbage outputs and reversible gates. Minimizing the number of garbage is very noticeable. In the present paper, we show a design of the reversible comparator based on the quantum gates implementation of the reversible DG gate. The reversible DG gate is designed by using 3 × 3 quantum gates such as NOT, CNOT, Controlled-V and Controlled-V+ gates. Also, we have used the TR gate and various types of quantum gates in the implementation results. Low power three-bit comparator is designed using DG Gate, New Gate and Fredkin Gate. In order to evaluate the benefit of using the DG gate proposed in this paper, one-bit comparator is constructed. The design is useful for the future computing techniques like quantum computers. The proposed designs are implemented using VHDL and functionally investigated using Quartus II simulator.
文摘To fill the continuous needs for faster processing elements with less power consumption causes large pressure on the complementary metal oxide semiconductor(CMOS)technology developers.The scaling scenario is not an option nowadays and other technologies need to be investigated.The quantum-dot cellular automata(QCA)technology is one of the important emerging nanotechnologies that have attracted much researchers’attention in recent years.This technology has many interesting features,such as high speed,low power consumption,and small size.These features make it an appropriate alternative to the CMOS technique.This paper suggests three novel structures of XNOR gates in the QCA technology.The presented structures do not follow the conventional approaches to the logic gates design but depend on the inherent capabilities of the new technology.The proposed structures are used as the main building blocks for a single-bit comparator.The resulted circuits are simulated for the verification purpose and then compared with existing counterparts in the literature.The comparison results are encouraging to append the proposed structures to the library of QCA gates.
基金National Science and Technology Major Projects for ‘Major New Drugs Innovation and Development’(Grant No.2017ZX09101001,Beijing,China)
文摘It is vital segment to choose the right comparator product during the development and study of generic medicinal product, and this is also definitely specified in the relevant documents from the China Food and Drug Administration (CFDA)that the comparator product should be innovator product or internationally recognized same medicinal product,which is used in the re-evaluation of generic medicinal product or marketed authorization application of the generic medicinal product.To facilitate the domestic and foreign pharmaceutical enterprises to choose and determine comparator product,four medicinal product evaluation procedures,as well as the corresponding marketed medicinal product list,are detailed elaborated in this paper.At the same time, by taking the Mifepristone Tablet (200mg)as example,the search and determination process of the comparator product for generic medicinal product application in the EU is illustrated with the combination of different marketed medicinal product lists.
文摘There are magnetic interference problems in the applications of DC current comparator. Analysis on the magnetic effectiveness which is applied by the external magnetic field is introduced in this paper. The effectiveness is proved by the actual results which are compared with the magnetic- circuit method and the finite element method. In addition, the reference comment is given which can be used in the practical work of DC current comparator shield design.
文摘Objective: We aim to analyze the surgical nursery of abdominal wall hernias in adults between two poorly fitted medical environments, the Regional Hospital Center of Tsévié (RHC-T) and the Prefectural Hospital Center of Kpalimé (PHC-K) in Togo. Methodology: It was a retrospective, descriptive and comparative study carried out over five years (2018-2022) focusing on abdominal wall hernias in adults. Information was gathered from the patients’clinical notes and registers on the frequency of hernias, the anatomo-clinical forms of hernias, the type of anesthesia, the hernia repair technique and the postoperative evolution. Results: Of the 1022 and 1026 operations performed, 312 and 412 were hernial repairs, representing 30.5% and 41.2% of operations at RHC-T and PHC-K respectively (p = 0.001). The inguinal hernia was the most often found in 83.7% (n = 261) at RHC-T versus 76.6% (n = 324) at PHC-K. Herniorrhaphy was the most frequently used repair method, in 93.6% (n = 292) of patients at RHC-T and in 91.3% (n = 376) at PHC-K (p = 0.11). Postoperative complications were noted in 5.1% of cases (n = 16) at RHC-T versus 3.5% of cases (n = 15) at PHC-K (p = 0.307). These complications included scrotal hematomas, surgical areas infections, and orchitis. We recorded 1.3% (n = 4) and 0.8% (n = 3) deaths at RHC-T and PHC-K respectively (p = 0.496). Conclusion: There is homogeneity in the treatment of hernia in these two hospitals in Togo.
基金the Natural Science Foundation of Shandong Province(ZR2020QC022)the Science and Technology Basic Resources Investigation Program of China(No.2019FY100900)+2 种基金the Major Program for Basic Research Project of Yunnan Province(202401BC070001)Yunnan Revitalization Talent Support Program:Yunling Scholar Project to Tingshuang Yithe open research project of“Cross Cooperative Team”of the Germplasm Bank of Wild Species,Kunming Institute of Botany,Chinese Academy of Sciences.
文摘The plastid genome(plastome)represents an indispensable molecular resource for studying plant phylogeny and evolution.Although plastome size is much smaller than that of nuclear genomes,accurately and efficientlyannotating and utilizing plastome sequences remain challenging.Therefore,a streamlined phylogenomic pipeline spanning plastome annotation,phylogenetic reconstruction and comparative genomics would greatly facilitate research utilizing this important organellar genome.Here,we develop PlastidHub,a novel web application employing innovative tools to analyze plastome sequences.In comparison with existing tools,key novel functionalities in PlastidHub include:(1)standardization of quadripartite structure;(2)improvement of annotation flexibility and consistency;(3)quantitative assessment of annotation completeness;(4)diverse extraction modes for canonical and specialized sequences;(5)intelligent screening of molecular markers for biodiversity studies;(6)genelevel visual comparison of structural variations and annotation completeness.PlastidHub features cloud-based web applications that do not require users to install,update,or maintain tools;detailed help documents including user guides,test examples,a static pop-up prompt box,and dynamic pop-up warning prompts when entering unreasonable parameter values;batch processing capabilities for all tools;intermediate results for secondary use;and easy-to-operate task flows between fileupload and download.A key feature of PlastidHub is its interrelated task-based user interface design.Give that PlastidHub is easy to use without specialized computational skills or resources,this new platform should be widely used among botanists and evolutionary biologists,improving and expediting research employing the plastome.PlastidHub is available at https://www.plastidhub.cn.
基金supported by the Shandong Natural Science Foundation Youth Project(No.ZR2023QE075)the Open Project Program of Shandong Marine Aerospace Equipment Technological Innovation Center(No.MAETIC202210)the Shandong Natural Science Foundation Project(No.ZR2022ME145)。
文摘The oscillating hydrofoil represents a promising technology for harvesting energy from tidal currents.While previous research has primarily focused on oscillating hydrofoils utilizing a fully activated control strategy,the industry predominantly employs a semi-activated control strategy in existing tidal current energy converters.It is essential to identify the differences in predicted energy-harvesting performance between these two controlling strategies through experimental modeling or numerical studies.Furthermore,the suitability of the fully activated control strategy in predicting the energy-harvesting capabilities of oscillating hydrofoils is evaluated.The 2D numerical models of hydrofoil based on fully activated and semi-activated control strategies have been developed and validated.The amplitudes of heaving and pitching movements for the fully activated hydrofoil are determined to match those of the semi-activated hydrofoil.The results show that the main difference between the two control strategies lies in the phase shift occurring between the pitching and heaving motions.This phase shift affects the lift force and its coordination with the heaving velocity,which in turn affects the power output.Notably,the maximum relative efficiency difference obtained between the fully activated and semi-activated control strategies can reach 191%.
基金Supported by the National Natural Science Foundation of China(Nos.91858208,92358301)the Laoshan Laboratory(No.LSKJ 202203500),the China Postdoctoral Science Foundation of China(No.2019M663209)the Fundamental Research Funds for the Central Universities in China(No.19lGPY100)。
文摘Bathymodiolus mussels distribute in both deep-sea cold seep and hydrothermal vent environments,whose endosymbiotic gill tissue is a prominent character for the adaptation of extreme habitats.However,few studies explored the adaptation mechanisms through comparative transcriptome sequencing and analysis of different tissues between seep mussels and vent mussels.We performed the comparative transcriptome sequencing and analysis for three tissue types(gill,mantle,and adductor muscle)of Bathymodiolus mussels collected from a cold seeping site Station S 11 and the 50-km away hydrothermal field Minami-Ensei Knoll in the Okinawa Trough.Results show that gene expression patterns had distinct tissue specificity.Compared with the non-endosymbiotic tissues(mantle and adductor muscle),the significantly strengthened gene functions in endosymbiotic gill included microbial recognition(fibrinogen C domain-containing protein 1-B-like(fibcd),fibrinogen-related protein 8(frp),peptidoglycan recognition proteins(pgrp),and C-type lectin(clec)),cell apoptosis and immunity(interferon regulatory factor 1/2-like 1(ir f),cathepsin D(ctsd),caspase 2(casp 2)),and antioxidant capacity(copper/zinc superoxide dismutase(czsod),glutathione peroxidase(gpx),selenoprotein(sel)),in both seep and vent individuals.Consistent with metal accumulation,high expression levels of genes related to heavy metal detoxification(cytochrome P 450(cyp),ferritin-like(ftl),metallothionein(mt),glutathione S-transferase(gst))were also observed in gill.Moreover,to adapt to high hydrostatic pressure in the deep sea,the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways associated with cellular community were significantly enriched in all three tissues,suggesting the regulation of cell structure and cell adhesion at transcriptional level.This study obtained gene expression profiles of deep-sea mussels subsisting at cold seep and hydrothermal vent sites,which could lay foundations for comprehensive investigations of molecular basis in adaptation of deep-sea mussels to the two extreme ecosystems.
基金supported by the National Key Research and Development Project(2022YFD2100703)the National Natural Science Foundation of China(32394051 and U23A20259)the Fundamental Research Funds for the Central Universities(JUSRP622013).
文摘Lactococcus lactis,a major starter culture in the dairy industry,has been widely applied in food fermentation.While current research has primarily focused on evaluating its role during fermentation,genomic investigations into its genetic diversity and functional adaptability remain limited.In this study,199 L.lactis strains isolated from Chinese traditional artisanal cheeses(72 bovine,71 goat,and 56 yak milk cheese isolates)were subjected to comparative genomic analysis.Genomic characteristic analysis indicated that bovine milk strains possess larger genomes and the highest number of unique genes.Functional characterization further demonstrated notable differences in carbohydrate metabolism among strains from different sources,with yak milk strains enriched in enzymes involved in complex polysaccharide degradation,including members of the carbohydrate esterases family.Moreover,strains from different sources exhibit distinct strategies for lactose hydrolysis and metabolic utilization,reflecting adaptive evolution to their specific nutritional niches.Analysis of the antibiotic resistance profile suggests that L.lactis predominantly harbors glycopeptide and lincosamide resistance genes,encompassing four distinct resistance mechanisms.Collectively,this study reveals the genetic diversity and adaptive evolution of L.lactis strains from different sources and identifies key genes associated with carbohydrate degradation,lactose metabolism,and antibiotic resistance,providing concrete genetic evidence for the selection of efficient and safe industrial fermentation strains.
文摘Although previous studies have analyzed the unique structural characteristics of the polar vortices on Earth,Venus,Mars,and Titan,the understanding of the polar vortices on Venus and Titan is primarily based on small-scale case studies due to the limited resolution and coverage of observational data.Conducting a detailed comparison of the polar vortex characteristics between the major terrestrial planets and Titan in the solar system is more challenging.In order to more finely compare the polar vortex characteristics of the main terrestrial planets in the solar system with Titan,we have achieved the optimal estimation of the polar vortices of Venus and Titan under existing conditions based on the advanced VCD2.3 and TitanWRF model.At the same time,combining ERA5 and EMARS databases,a detailed spatiotemporal comparison of polar vortex characteristics between terrestrial planets with atmospheres in the solar system and the most Earth-like Titan satellite was conducted for the first time.Here,we demonstrate that:(1)The circulation characteristics of Mars above the 1 mbar level are very similar to those at 1000 mbar in the lower layers of Titan,with seasonal variations of the same height.(2)In contrast to the vortex structure that is stably maintained in the lead direction in the polar regions of Mars and Earth during the winter,the time of occurrence of the peak vortex intensity at Titan and Venus is gradually shifted forward with increasing altitude.(3)When Venus undergoes vortex instability drift,the polar vortex at an altitude of 1 mbar breaks up into banded structures,a phenomenon that closely resembles the twisting deformation of PV structures during weak stratospheric polar vortex events on Earth.
文摘This paper conducts clustering,potential semantic indexing,comparison,and inductive analysis of research papers on marketing between China and the UK from January 2020 to September 2024.The study found that the Chinese marketing research focuses on digital transformation,policy impact,value co-creation,and emerging e-commerce models.In contrast,the UK marketing research focuses more on sustainability,technology integration,real-time research,and personalized marketing strategies.The study also found that there were few marketing articles published in Chinese and CSSCI journals in China,while the SSCI journals published in English were 62 times more than in Chinese.According to the research,digital marketing and data-driven decision-making,diversified marketing channels,sustainability and circular economy,technological innovation and cutting-edge technology application,meta-universe and blockchain technology,AI+marketing development,brand building,and international market expansion will become the research hotspots in the field of marketing in the future.The research suggests that China should strengthen the construction of an academic marketing platform,and China and the UK should strengthen cooperation in marketing research,learn from each other's strengths,and jointly give full play to their advantages in technology application,market and economy,strategy and innovation,and social media,to contribute to global economic development and marketing research.
