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ATSSC:An Attack Tolerant System in Serverless Computing
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作者 Zhang Shuai Guo Yunfei +2 位作者 Hu Hongchao Liu Wenyan Wang Yawen 《China Communications》 SCIE CSCD 2024年第6期192-205,共14页
Serverless computing is a promising paradigm in cloud computing that greatly simplifies cloud programming.With serverless computing,developers only provide function code to serverless platform,and these functions are ... Serverless computing is a promising paradigm in cloud computing that greatly simplifies cloud programming.With serverless computing,developers only provide function code to serverless platform,and these functions are invoked by its driven events.Nonetheless,security threats in serverless computing such as vulnerability-based security threats have become the pain point hindering its wide adoption.The ideas in proactive defense such as redundancy,diversity and dynamic provide promising approaches to protect against cyberattacks.However,these security technologies are mostly applied to serverless platform based on“stacked”mode,as they are designed independent with serverless computing.The lack of security consideration in the initial design makes it especially challenging to achieve the all life cycle protection for serverless application with limited cost.In this paper,we present ATSSC,a proactive defense enabled attack tolerant serverless platform.ATSSC integrates the characteristic of redundancy,diversity and dynamic into serverless seamless to achieve high-level security and efficiency.Specifically,ATSSC constructs multiple diverse function replicas to process the driven events and performs cross-validation to verify the results.In order to create diverse function replicas,both software diversity and environment diversity are adopted.Furthermore,a dynamic function refresh strategy is proposed to keep the clean state of serverless functions.We implement ATSSC based on Kubernetes and Knative.Analysis and experimental results demonstrate that ATSSC can effectively protect serverless computing against cyberattacks with acceptable costs. 展开更多
关键词 active defense attack tolerant cloud computing SECURITY serverless computing
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Active Fault Tolerant Nonsingular Terminal Sliding Mode Control for Electromechanical System Based on Support Vector Machine
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作者 Jian Hu Zhengyin Yang Jianyong Yao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期189-203,共15页
Effective fault diagnosis and fault-tolerant control method for aeronautics electromechanical actuator is concerned in this paper.By borrowing the advantages of model-driven and data-driven methods,a fault tolerant no... Effective fault diagnosis and fault-tolerant control method for aeronautics electromechanical actuator is concerned in this paper.By borrowing the advantages of model-driven and data-driven methods,a fault tolerant nonsingular terminal sliding mode control method based on support vector machine(SVM)is proposed.A SVM is designed to estimate the fault by off-line learning from small sample data with solving convex quadratic programming method and is introduced into a high-gain observer,so as to improve the state estimation and fault detection accuracy when the fault occurs.The state estimation value of the observer is used for state reconfiguration.A novel nonsingular terminal sliding mode surface is designed,and Lyapunov theorem is used to derive a parameter adaptation law and a control law.It is guaranteed that the proposed controller can achieve asymptotical stability which is superior to many advanced fault-tolerant controllers.In addition,the parameter estimation also can help to diagnose the system faults because the faults can be reflected by the parameters variation.Extensive comparative simulation and experimental results illustrate the effectiveness and advancement of the proposed controller compared with several other main-stream controllers. 展开更多
关键词 Aeronautics electromechanical actuator Fault tolerant control Support vector machine State observer Parametric uncertainty
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Drought-Tolerant Rice at Molecular Breeding Eras:An Emerging Reality
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作者 ZHU Chengqi YE Yuxuan +3 位作者 QIU Tian HUANG Yafan YING Jifeng SHEN Zhicheng 《Rice science》 SCIE CSCD 2024年第2期179-189,共11页
Rice(Oryza sativa L.)stands as the most significantly influential food crop in the developing world,with its total production and yield stability affected by environmental stress.Drought stress impacts about 45%of the... Rice(Oryza sativa L.)stands as the most significantly influential food crop in the developing world,with its total production and yield stability affected by environmental stress.Drought stress impacts about 45%of the world’s rice area,affecting plants at molecular,biochemical,physiological,and phenotypic levels.The conventional breeding method,predominantly employing single pedigree selection,has been widely utilized in breeding numerous drought-tolerant rice varieties since the Green Revolution.With rapid progress in plant molecular biology,hundreds of drought-tolerant QTLs/genes have been identified and tested in rice crops under both indoor and field conditions.Several genes have been introgressed into elite germplasm to develop commercially accepted drought-tolerant varieties,resulting in the development of several drought-tolerant rice varieties through marker-assisted selection and genetically engineered approaches.This review provides up-to-date information on proof-of-concept genes and breeding methods in the molecular breeding era,offering guidance for rice breeders to develop drought-tolerant rice varieties. 展开更多
关键词 conventional breeding drought stress drought tolerant rice genetic engineering marker-assisted selection breeding
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Quantum generative adversarial networks based on a readout error mitigation method with fault tolerant mechanism
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作者 赵润盛 马鸿洋 +2 位作者 程涛 王爽 范兴奎 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期285-295,共11页
Readout errors caused by measurement noise are a significant source of errors in quantum circuits,which severely affect the output results and are an urgent problem to be solved in noisy-intermediate scale quantum(NIS... Readout errors caused by measurement noise are a significant source of errors in quantum circuits,which severely affect the output results and are an urgent problem to be solved in noisy-intermediate scale quantum(NISQ)computing.In this paper,we use the bit-flip averaging(BFA)method to mitigate frequent readout errors in quantum generative adversarial networks(QGAN)for image generation,which simplifies the response matrix structure by averaging the qubits for each random bit-flip in advance,successfully solving problems with high cost of measurement for traditional error mitigation methods.Our experiments were simulated in Qiskit using the handwritten digit image recognition dataset under the BFA-based method,the Kullback-Leibler(KL)divergence of the generated images converges to 0.04,0.05,and 0.1 for readout error probabilities of p=0.01,p=0.05,and p=0.1,respectively.Additionally,by evaluating the fidelity of the quantum states representing the images,we observe average fidelity values of 0.97,0.96,and 0.95 for the three readout error probabilities,respectively.These results demonstrate the robustness of the model in mitigating readout errors and provide a highly fault tolerant mechanism for image generation models. 展开更多
关键词 readout errors quantum generative adversarial networks bit-flip averaging method fault tolerant mechanisms
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An Environment‑Tolerant Ion‑Conducting Double‑Network Composite Hydrogel for High‑Performance Flexible Electronic Devices 被引量:4
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作者 Wenchao Zhao Haifeng Zhou +3 位作者 Wenkang Li Manlin Chen Min Zhou Long Zhao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期352-369,共18页
High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic devices.However,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use i... High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic devices.However,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use in soft electronics.To resolve these issues,a method involving freeze–thawing and ionizing radiation technology is reported herein for synthesizing a novel double-network(DN)ICH based on a poly(ionic liquid)/MXene/poly(vinyl alcohol)(PMP DN ICH)system.The well-designed ICH exhibits outstanding ionic conductivity(63.89 mS cm^(-1) at 25℃),excellent temperature resistance(-60–80℃),prolonged stability(30 d at ambient temperature),high oxidation resist-ance,remarkable antibacterial activity,decent mechanical performance,and adhesion.Additionally,the ICH performs effectively in a flexible wireless strain sensor,thermal sensor,all-solid-state supercapacitor,and single-electrode triboelectric nanogenerator,thereby highlighting its viability in constructing soft electronic devices.The highly integrated gel structure endows these flexible electronic devices with stable,reliable signal output performance.In particular,the all-solid-state supercapacitor containing the PMP DN ICH electrolyte exhibits a high areal specific capacitance of 253.38 mF cm^(-2)(current density,1 mA cm^(-2))and excellent environmental adaptability.This study paves the way for the design and fabrication of high-performance mul-tifunctional/flexible ICHs for wearable sensing,energy-storage,and energy-harvesting applications. 展开更多
关键词 Ionic liquids Double-network hydrogels Temperature tolerance Multifunctionality Flexible electronic devices
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Making wheat salt tolerant:What is missing? 被引量:1
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作者 Lukasz Kotula Noreen Zahra +2 位作者 Muhammad Farooq Sergey Shabala Kadambot H.M.Siddique 《The Crop Journal》 SCIE CSCD 2024年第5期1299-1308,共10页
The growing global population presents a significant challenge to ensuring food security,further compounded by the increasing threat of salinity to agricultural productivity.Wheat,a major staple food providing 20%of t... The growing global population presents a significant challenge to ensuring food security,further compounded by the increasing threat of salinity to agricultural productivity.Wheat,a major staple food providing 20%of the total caloric intake for humans,is susceptible to salinity stress.Developing new salttolerant wheat cultivars using wheat breeding techniques and genetic modifications is crucial to addressing this issue while ensuring the sustainability and efficiency of wheat production systems within the prevailing climate trend.This review overviews the current landscape in this field and explores key mechanisms and associated genetic traits that warrant attention within breeding programs.We contend that traditional approaches to breeding wheat for Na^(+)exclusion have limited applicability across varying soil salinity levels,rendering them inefficient.Moreover,we question current phenotyping approaches,advocating for a shift from whole-plant assessments to cell-based phenotyping platforms.Finally,we propose a broader use of wild wheat relatives and various breeding strategies to tap into their germplasm pool for inclusion in wheat breeding programs. 展开更多
关键词 PHENOTYPING BREEDING Reactive oxygen species Tissue tolerance Sodium exclusion Potassium retention
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Identification of genes involved in cadmium-ion tolerance in evolutionary Synechocystis sp.PCC 6803 tolerant to both cadmium and high light
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作者 Jie Xiong Zhengxin Dong +3 位作者 Yaru Xie Weiwen Zhang Tao Sun Lei Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第10期74-82,共9页
Photosynthetic cyanobacteria have shown great potential as“autotrophic cell factories”for the synthesis of fuels and chemicals.However,poor tolerance to various environmental stressors such as high light and heavy m... Photosynthetic cyanobacteria have shown great potential as“autotrophic cell factories”for the synthesis of fuels and chemicals.However,poor tolerance to various environmental stressors such as high light and heavy metals is an important factor limiting their economic viability.While numerous studies have focused on the tolerance mechanism of cyanobacteria to individual stressors,their response to simultaneous stresses remains to be recovered.To investigate the mechanism of cross tolerance to heavymetal Cd^(2+) and high light,the model cyanobacterium Synechocystis sp.PCC 6803 tolerant to both Cd^(2+) and high light was obtained via about 800 days’cross-adaptive laboratory evolution.Three evolutionary strains capable of tolerating both 5.5 μmol·L^(-1) Cd^(2+) and 600 μmol·m^(-2)·s^(-1) high light were successfully obtained,achieving about 83%enhancement of Cd^(2+) tolerance compared with the parent strain.The different response of parent and evolutionary strains to Cd^(2+) was elucidated via metabolomics.Furthermore,a total of 15 genes that were mutated during evolution were identified by whole-genome re-sequencing.Finally,by single-gene knockout and complementation analysis,four genes including ssl2615,sll1732,ssr1480,and sll1659 involved in the improvement of Cd^(2+) tolerance under high-light condition were successfully identified.This work explored the tolerance mechanism of Synechocystis sp.PCC 6803 to cadmium under high-light condition and provided valuable reference for deciphering multitolerance mechanism of cyanobacteria in the future. 展开更多
关键词 SYNECHOCYSTIS Adaptive laboratory evolution Cross tolerance Cadmium-ion tolerance
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Slippery hydrogel with desiccation-tolerant‘skin’for high-precision additive manufacturing
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作者 Desheng Liu Pan Jiang +6 位作者 Yue Hu Yaozhong Lu Yixian Wang Jiayu Wu Danli Hu Tao Wu Xiaolong Wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期486-500,共15页
Hydrogels inevitably undergo dehydration,structural collapse,and shrinkage deformation due to the uninterrupted evaporation in the atmosphere,thereby losing their flexibility,slipperiness,and manufacturing precision.H... Hydrogels inevitably undergo dehydration,structural collapse,and shrinkage deformation due to the uninterrupted evaporation in the atmosphere,thereby losing their flexibility,slipperiness,and manufacturing precision.Here,we propose a novel bioinspired strategy to construct a spontaneously formed‘skin’on the slippery hydrogels by incorporating biological stress metabolites trehalose into the hydrogel network,which can generate robust hydrogen bonding interactions to restrain water evaporation.The contents of trehalose in hydrogel matrix can also regulate the desiccation-tolerance,mechanical properties,and lubricating performance of slippery hydrogels in a wide range.Combining vat photopolymerization three-dimensional printing and trehalose-modified slippery hydrogels enables to achieve the structural hydrogels with high resolution,shape fidelity,and sophisticated architectures,instead of structural collapse and shrinkage deformation caused by dehydration.And thus,this proposed functional hydrogel adapts to manufacture large-scale hydrogels with sophisticated architectures in a long-term process.As a proof-of-concept demonstration,a high-precision and sophisticated slippery hydrogel vascular phantom was easily fabricated to imitate guidewire intervention.Additionally,the proposed protocol is universally applicable to diverse types of hydrogel systems.This strategy opens up a versatile methodology to fabricate dry-resistant slippery hydrogel for functional structures and devices,expanding their high-precision processing and broad applications in the atmosphere. 展开更多
关键词 slippery hydrogel TREHALOSE desiccation tolerance vat photopolymerization 3D printing hydrogen bonding
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Advances in Understanding Cadmium Stress and Breeding of Cadmium-Tolerant Crops
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作者 LIANG Liang WANG Chenchang CHEN Tao 《Rice science》 SCIE CSCD 2024年第5期507-525,共19页
Cadmium(Cd) pollution has emerged as a critical global environmental concern, due to its significant toxicity, environmental persistence, and the pervasiveness of contamination. Significantly, the bioaccumulation of C... Cadmium(Cd) pollution has emerged as a critical global environmental concern, due to its significant toxicity, environmental persistence, and the pervasiveness of contamination. Significantly, the bioaccumulation of Cd in agricultural crops constitutes a primary vector for its entry into the human diet. This issue warrants urgent attention from both the scientific community and policymakers to develop and implement effective mitigation strategies. This review delves into the physiological impacts of Cd stress on plants, including the suppression of photosynthetic activity, amplification of oxidative stress, and disruptions in mineral nutrient homeostasis. Additionally, the resistance mechanisms deployed by plants in response to Cd stress have been explored, and the prospective contributions of molecular breeding strategies in augmenting crop tolerance to Cd and minimizing its bioaccumulation have been assessed. By integrating and analyzing these findings, we seek to inform future research trajectories and proffer strategic approaches to enhance agricultural sustainability, safeguard human health, and protect environmental integrity. 展开更多
关键词 cadmium stress crop tolerance physiological response molecular breeding strategy
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A Fault-Tolerant Mobility-Aware Caching Method in Edge Computing
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作者 Yong Ma Han Zhao +5 位作者 Kunyin Guo Yunni Xia Xu Wang Xianhua Niu Dongge Zhu Yumin Dong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期907-927,共21页
Mobile Edge Computing(MEC)is a technology designed for the on-demand provisioning of computing and storage services,strategically positioned close to users.In the MEC environment,frequently accessed content can be dep... Mobile Edge Computing(MEC)is a technology designed for the on-demand provisioning of computing and storage services,strategically positioned close to users.In the MEC environment,frequently accessed content can be deployed and cached on edge servers to optimize the efficiency of content delivery,ultimately enhancing the quality of the user experience.However,due to the typical placement of edge devices and nodes at the network’s periphery,these components may face various potential fault tolerance challenges,including network instability,device failures,and resource constraints.Considering the dynamic nature ofMEC,making high-quality content caching decisions for real-time mobile applications,especially those sensitive to latency,by effectively utilizing mobility information,continues to be a significant challenge.In response to this challenge,this paper introduces FT-MAACC,a mobility-aware caching solution grounded in multi-agent deep reinforcement learning and equipped with fault tolerance mechanisms.This approach comprehensively integrates content adaptivity algorithms to evaluate the priority of highly user-adaptive cached content.Furthermore,it relies on collaborative caching strategies based onmulti-agent deep reinforcement learningmodels and establishes a fault-tolerancemodel to ensure the system’s reliability,availability,and persistence.Empirical results unequivocally demonstrate that FTMAACC outperforms its peer methods in cache hit rates and transmission latency. 展开更多
关键词 Mobile edge networks MOBILITY fault tolerance cooperative caching multi-agent deep reinforcement learning content prediction
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Graph Attention Residual Network Based Routing and Fault-Tolerant Scheduling Mechanism for Data Flow in Power Communication Network
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作者 Zhihong Lin Zeng Zeng +3 位作者 Yituan Yu Yinlin Ren Xuesong Qiu Jinqian Chen 《Computers, Materials & Continua》 SCIE EI 2024年第10期1641-1665,共25页
For permanent faults(PF)in the power communication network(PCN),such as link interruptions,the timesensitive networking(TSN)relied on by PCN,typically employs spatial redundancy fault-tolerance methods to keep service... For permanent faults(PF)in the power communication network(PCN),such as link interruptions,the timesensitive networking(TSN)relied on by PCN,typically employs spatial redundancy fault-tolerance methods to keep service stability and reliability,which often limits TSN scheduling performance in fault-free ideal states.So this paper proposes a graph attention residual network-based routing and fault-tolerant scheduling mechanism(GRFS)for data flow in PCN,which specifically includes a communication system architecture for integrated terminals based on a cyclic queuing and forwarding(CQF)model and fault recovery method,which reduces the impact of faults by simplified scheduling configurations of CQF and fault-tolerance of prioritizing the rerouting of faulty time-sensitive(TS)flows;considering that PF leading to changes in network topology is more appropriately solved by doing routing and time slot injection decisions hop-by-hop,and that reasonable network load can reduce the damage caused by PF and reserve resources for the rerouting of faulty TS flows,an optimization model for joint routing and scheduling is constructed with scheduling success rate as the objective,and with traffic latency and network load as constraints;to catch changes in TSN topology and traffic load,a D3QN algorithm based on a multi-head graph attention residual network(MGAR)is designed to solve the problem model,where the MGAR based encoder reconstructs the TSN status into feature embedding vectors,and a dueling network decoder performs decoding tasks on the reconstructed feature embedding vectors.Simulation results show that GRFS outperforms heuristic fault-tolerance algorithms and other benchmark schemes by approximately 10%in routing and scheduling success rate in ideal states and 5%in rerouting and rescheduling success rate in fault states. 展开更多
关键词 Time-sensitive network deep reinforcement learning graph attention network fault tolerance
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Comparison of Some Characteristics Between Phragmites communis and Its Salt Tolerant Variant 被引量:8
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作者 许祥明 叶和春 +1 位作者 李国凤 陈建林 《Acta Botanica Sinica》 CSCD 2000年第11期1126-1130,共5页
R5002_12, a salt tolerant line of Phragmites communis Trin., which was obtained from ethyl methane sulfonate (EMS) treated callus selected under saline stress, was compared with its wild line in respect to their m... R5002_12, a salt tolerant line of Phragmites communis Trin., which was obtained from ethyl methane sulfonate (EMS) treated callus selected under saline stress, was compared with its wild line in respect to their molecular biological, physiological and biochemical characterizations. Five arbitrary primers were screened which showed differences in DNA amplified polymorphism between the variant and its wild line. Some new proteins appeared in the salt tolerant plant under salt stress. Electrophoresis of peroxidase and esterase also showed some differences in isozyme expression between them. The chlorophyll content of the variant was higher than that of the original variety, whether the plants were under salt stress or not. 展开更多
关键词 Phragmites communis salt tolerant variant RAPD ISOZYME CHLOROPHYLL soluble protein
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FAULT-TOLERANT INTEGRATED NAVIGATION SYSTEM BASED ON NEURONS 被引量:1
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作者 马昕 袁信 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期4-7,共4页
In this paper, the multisensor data fusion technique of a fault tolerant integrated navigation system is discussed. A neural approach for data fusion is proposed for multisensor integrated systems. The simulation res... In this paper, the multisensor data fusion technique of a fault tolerant integrated navigation system is discussed. A neural approach for data fusion is proposed for multisensor integrated systems. The simulation results show that this neural approach for data fusion is feasible. 展开更多
关键词 navigation system NEURON data fusion fault tolerant
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Fault tolerant control of electric pitch control system based on single current detection
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作者 李宏伟 付勃 +2 位作者 董海鹰 杨立霞 王睿敏 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期63-70,共8页
In view of the current sensors failure in electric pitch system,a variable universe fuzzy fault tolerant control method of electric pitch control system based on single current detection is proposed.When there is sing... In view of the current sensors failure in electric pitch system,a variable universe fuzzy fault tolerant control method of electric pitch control system based on single current detection is proposed.When there is single or two-current sensor fault occurs,based on the proposed method the missing current information can be reconstructed by using direct current(DC)bus current sensor and the three-phase current can be updated in time within any two adjacent sampling periods,so as to ensure stability of the closed-loop system.And then the switchover and fault tolerant control of fault current sensor would be accomplished by fault diagnosis method based on adaptive threshold judgment.For the reconstructed signal error caused by the modulation method and the main control target of electric pitch system,a variable universe fuzzy control method is used in the speed loop,which can improve the anti-disturbance ability to load variation,and the robustness of fault tolerance system.The results show that the fault tolerant control method makes the variable pitch control system still has ideal control characteristics in case of sensor failure although part of the system performance is lost,thus the correctness of the proposed method is verified. 展开更多
关键词 electric pitch control fault tolerant control variable universe fuzzy control single current detection
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Starch RVA Profile Properties for Cold Tolerant and Sensitive Cultivars of Japonica Rice at Different Altitudes 被引量:5
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作者 朱振华 金基永 +6 位作者 袁平荣 赵国珍 苏振喜 世荣 邹茜 杨世准 戴陆园 《Agricultural Science & Technology》 CAS 2011年第12期1831-1836,共6页
[Objective] By investigating of change rule rice starch RVA profile properties and the influence of cold tolerance on rice quality,the aim was to provide scientific references to the breeding of new cold-tolerant japo... [Objective] By investigating of change rule rice starch RVA profile properties and the influence of cold tolerance on rice quality,the aim was to provide scientific references to the breeding of new cold-tolerant japonica rice varieties with high quality in the Yunnan plateau.[Method] Four cold-tolerant and five cold-sensitive japonica rice cultivars were grown at three locations with different altitudes in Yunnan plateau to investigate rice starch RVA profile characteristics.[Result] The results showed that with increasing altitude,the setback viscosity in cold-sensitive cultivars increased significantly,while the peak viscosity and breakdown viscosity decreased significantly.However,the peak viscosity and breakdown viscosity in cold-tolerant cultivars initially decreased and then gradually increased with rising altitude,whereas the setback viscosity initially increased and then decreased.[Conclusion] The starch RVA parameters of cold-tolerant cultivars were less sensitive to different environments than those of cold-sensitive cultivars.Cooking and eating quality of cold-tolerant cultivars had relatively stable trends with rising altitude,whereas cooking and eating quality of cold-sensitive cultivars had a trend toward inferior. 展开更多
关键词 Japonica rice Cold tolerance Rice quality Starch viscosity ALTITUDE
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Screening of Drought-tolerant Brassica napus L.Varieties and Analysis on Their Physiologic and Biochemical Variations under Drought Stress 被引量:7
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作者 李淑娟 程量 +3 位作者 彭少丹 陈升位 王勤方 林良斌 《Agricultural Science & Technology》 CAS 2014年第4期596-604,615,共10页
[Objective] The aim of this study was to screen drought-tolerant Brassica napus L. germplasm resources by analyzing their physiological and biochemical changes under drought stress. [Method] Forty varieties of B. napu... [Objective] The aim of this study was to screen drought-tolerant Brassica napus L. germplasm resources by analyzing their physiological and biochemical changes under drought stress. [Method] Forty varieties of B. napus varieties were cultured under PEG-6000 osmotic stress and extreme drought stress in pots, re- spectively. Then, the contents of chlorophyll, carotenoid, proline, malondialdehyde (MDA), soluble sugar, soluble protein, and the activities of superoxide dismutase (SOD), catalase(CAT), peroxidase(POD) were measured under drought stress. [Result] Sever- al drought-tolerant varieties of B. napus were screened out: YAU200908, Xiangyou No.15, YAU200903, YAU200907, YAU200906 and YAU200904. Physiological and biochemical analysis showed that, the contents of chlorophyll and carotenoid de- creased with drought stress increasing; the contents of proline, soluble sugar, solu- ble protein, MDA and the activities of SOD,CAT, POD raised with drought stress in- creasing. [Conclusion] In the rapeseed varieties with stronger drought tolerance, the decrease in carotenoid content and the increase in proline content, soluble sugar content, MDA content, SOD activity, CAT activity were more obvious, so all these physiological and biochemical indices can be used to evaluate the drought tolerance of rapeseed. 展开更多
关键词 Brassica napus L. Drought tolerance Drought stress Physiologic and biochemical changes
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Effects of High Temperature Stress on Growth of Stress-Tolerant Rice Seedlings with Resistibility 被引量:4
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作者 张晓晶 张思远 +1 位作者 李春青 张文会 《Agricultural Science & Technology》 CAS 2014年第4期576-578,584,共4页
Two heat-tolerant rice varieties, N5 and TQ, were chosen as test materi- als. Specifically, rice seedlings (leaf age at 2.1), cultivated in room, were treated at 40 ℃ for 7 d and some indices were measured, includi... Two heat-tolerant rice varieties, N5 and TQ, were chosen as test materi- als. Specifically, rice seedlings (leaf age at 2.1), cultivated in room, were treated at 40 ℃ for 7 d and some indices were measured, including plant height, dry weight, leaf color, proline, malondialdehyde and conductivity. The results showed that high temperature advanced the growth of N5 seedlings, for example, plant height, root length and dry weight of ground parts all increased. However, high temperature prevented TQ seedlings growth, plant height in particular. Furthermore, high temper- ature treatment increased the content of chlorophyll of N5 and had none effects on PSII of N5, with little damages on membrane system. On the other hand, high temperature actually reduced PSII activity of TQ, and seriously damaged TQ mem- brane system. It is speculated that the differences of the two varieties lie on pro- duction or removing capacity of reactive oxide species. 展开更多
关键词 High temperature stress Rice seedlings TOLERANCE
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Screening and Evaluation of Salt Tolerant Varieties in Peanut 被引量:3
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作者 沈一 刘永惠 陈志德 《Agricultural Science & Technology》 CAS 2014年第4期542-545,共4页
The selection and application of salt tolerance varieties in peanut is impor- tant for the exploitation of saline soil. In this study, 41 peanut varieties were select- ed for the evaluation of salt tolerance in both g... The selection and application of salt tolerance varieties in peanut is impor- tant for the exploitation of saline soil. In this study, 41 peanut varieties were select- ed for the evaluation of salt tolerance in both germination and young seedling stage. The results showed the germination and growth of peanut were significantly inhibited by salt stress, which were enhanced by salt concentration increasing. The 0.5% NaCI was selected as the most suitable concentration for further identification, and the characters in germination stage (including the relative germination potential, relative germination rate and germination index) and young seedling stage (including relative main root length, seedling height, fresh weight, dry weight, et aL) were measured. Cluster analysis showed the varieties could be divided into different groups, and 9 and 3 salt-tolerant varieties were identified in the two stages, respec- tively, including two varieties performed well in both two stages, which could be useful for the breeding of new salt tolerance varieties and the study of salt toler- ance mechanism. 展开更多
关键词 PEANUT Salt tolerance EVALUATION Germination stage Young seedling stage
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Preparation and Catalytic Application of Novel Water Tolerant Solid Acid Catalysts of Zirconium Sulfate/HZSM-5 被引量:11
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作者 JIANG Ya-jie JUAN Joon Ching +3 位作者 MENG Xiu-juan CAO Wei-liang YARMO Mohd Ambar ZHANG Jing-chang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第3期349-354,共6页
Esterification of acrylic acid(AA) to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorptio... Esterification of acrylic acid(AA) to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorption, TGA-DTA, XPS, and ammonia adsorption FTIR. The effects of Si/Al ratio, zirconium sulfate(ZS) loading on HZSM-5 and calcination temperature on the esterification were investigated. When 20% (mass fraction) ZS is loaded on HZSM-5, the conversion of AA reaches 100%. XRD analysis indicates that ZS is highly dispersed on HZSM-5 because no crystalline structure assigned to ZS is found. Catalytic activity and hydrophobicity of ZS supported on HZSM-5 are higher compared with those of parent ZS or HZSM-5. Results show that this kind of novel catalysts is an efficient water tolerant solid acid catalyst for esterification reactions. 展开更多
关键词 Solid acid catalyst Zirconium sulfate HZSM-5 Esterification reaction Water tolerant
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Effect and Mechanism of Cold Tolerant Seed-Coating Agents on the Cold Tolerance of Early Indica Rice Seedlings 被引量:13
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作者 ZHANG Hai-qing ZOU Ying-bin XIAO Guo-chao XIONG Yuan-fu 《Agricultural Sciences in China》 CAS CSCD 2007年第7期792-801,共10页
To better understand the effect and mechanism of cold tolerant seed-coating agents on the cold tolerance of rice seedlings, the physiological and biochemical effects of four cold tolerant seed-coating agents (HET, YK... To better understand the effect and mechanism of cold tolerant seed-coating agents on the cold tolerance of rice seedlings, the physiological and biochemical effects of four cold tolerant seed-coating agents (HET, YKJ, YKZYJ, and the ABA seed coating agents) on two early indica rice varieties were studied under chilling stress. The results showed that the rice seedlings treated with cold tolerant seed-coating agents under chilling stress maintained dramatically higher root vigor, POD, CAT and SOD activities, and chlorophyll content, had lower MDA content and electrolyte leakage, and accumulated more soluble sugar and free proline, when compared with the control without the treatment, and finally showed lower plant injury rate. It was indicated that the cold tolerant seed coating agent improved the ability of rice seedlings in resisting to chilling stress. YKZYJ was ranked the first in terms of the efficiency in cold tolerance among the four cold tolerant seed-coating agents tested. 展开更多
关键词 RICE cold tolerant seed-coating agent chilling stress physiology and biochemistry mechanism of cold tolerance
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