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QBIoT:A Quantum Blockchain Framework for IoT with an Improved Proof-of-Authority Consensus Algorithm and a Public-Key Quantum Signature
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作者 ang liu Qing Zhang +3 位作者 Shengwei Xu Huamin Feng Xiu-bo Chen Wen liu 《Computers, Materials & Continua》 SCIE EI 2024年第7期1727-1751,共25页
The Internet of Things(IoT)is a network system that connects physical devices through the Internet,allowing them to interact.Nowadays,IoT has become an integral part of our lives,offering convenience and smart functio... The Internet of Things(IoT)is a network system that connects physical devices through the Internet,allowing them to interact.Nowadays,IoT has become an integral part of our lives,offering convenience and smart functionality.However,the growing number of IoT devices has brought about a corresponding increase in cybersecurity threats,such as device vulnerabilities,data privacy concerns,and network susceptibilities.Integrating blockchain technology with IoT has proven to be a promising approach to enhance IoT security.Nevertheless,the emergence of quantum computing poses a significant challenge to the security of traditional classical cryptography used in blockchain,potentially exposing it to quantum cyber-attacks.To support the growth of the IoT industry,mitigate quantum threats,and safeguard IoT data,this study proposes a robust blockchain solution for IoT that incorporates both classical and post-quantum security measures.Firstly,we present the Quantum-Enhanced Blockchain Architecture for IoT(QBIoT)to ensure secure data sharing and integrity protection.Secondly,we propose an improved Proof of Authority consensus algorithm called“Proof of Authority with Random Election”(PoARE),implemented within QBIoT for leader selection and new block creation.Thirdly,we develop a publickey quantum signature protocol for transaction verification in the blockchain.Finally,a comprehensive security analysis of QBIoT demonstrates its resilience against cyber threats from both classical and quantum adversaries.In summary,this research introduces an innovative quantum-enhanced blockchain solution to address quantum security concernswithin the realmof IoT.The proposedQBIoT framework contributes to the ongoing development of quantum blockchain technology and offers valuable insights for future research on IoT security. 展开更多
关键词 IOT quantum blockchain public-key quantum signature quantum hash function
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Mechanical criterion for coal and gas outburst:a perspective from multiphysics coupling 被引量:6
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作者 Ting liu Baiquan Lin +1 位作者 Xuehai Fu ang liu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第6期1423-1435,共13页
Although a series of hypotheses have been proposed,the mechanism underlying coal and gas outburst remains unclear.Given the low-index outbursts encountered in mining practice,we attempt to explore this mechanism using... Although a series of hypotheses have been proposed,the mechanism underlying coal and gas outburst remains unclear.Given the low-index outbursts encountered in mining practice,we attempt to explore this mechanism using a multiphysics coupling model considering the effects of coal strength and gas mass transfer on failure.Based on force analysis of coal ahead of the heading face,a risk identification index C_(m)and a critical criterion(C_(m)≥1)of coal instability are proposed.According to this criterion,the driving force of an outburst consists of stress and gas pressure gradients along the heading direction of the roadway,whereas resistance depends on the shear and tensile strengths of the coal.The results show that outburst risk decreases slightly,followed by a rapid increase,with increasing vertical stress,whereas it decreases with increasing coal strength and increases with gas pressure monotonically.Using the response surface method,a coupled multi-factor model for the risk identification index is developed.The results indicate strong interactions among the controlling factors.Moreover,the critical values of the factors corresponding to outburst change depending on the environment of the coal seams,rather than being constants.As the buried depth of a coal seam increases,the critical values of gas pressure and coal strength decrease slightly,followed by a rapid increase.According to its controlling factors,outburst can be divided into stress-dominated,coal-strength-dominated,gas-pressure-dominated,and multi-factor compound types.Based on this classification,a classified control method is proposed to enable more targeted outburst prevention. 展开更多
关键词 Coal and gas outburst Critical criterion Multiphysics coupling Response surface method
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Tuning the intermediate reaction barriers by a CuPd catalyst to improve the selectivity of CO_(2) electroreduction to C_(2) products 被引量:5
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作者 Li Zhu Yiyang Lin +8 位作者 ang liu Emiliano Cortés Hongmei Li Junhua Hu Akira Yamaguchi Xiaoliang liu Masahiro Miyauchi Junwei Fu Min liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第9期1500-1508,共9页
Electrochemical CO2 reduction is a promising strategy for the utilization of CO2 and intermittent excess electricity.Cu is the only single metal catalyst that can electrochemically convert CO2 into multicarbon product... Electrochemical CO2 reduction is a promising strategy for the utilization of CO2 and intermittent excess electricity.Cu is the only single metal catalyst that can electrochemically convert CO2 into multicarbon products.However,Cu exhibits an unfavorable activity and selectivity for the generation of C2 products because of the insufficient amount of CO*provided for the C‐C coupling.Based on the strong CO2 adsorption and ultrafast reaction kinetics of CO*formation on Pd,an intimate CuPd(100)interface was designed to lower the intermediate reaction barriers and improve the efficiency of C2 product formation.Density functional theory(DFT)calculations showed that the CuPd(100)interface enhanced the CO2 adsorption and decreased the CO2*hydrogenation energy barrier,which was beneficial for the C‐C coupling.The potential‐determining step(PDS)barrier of CO2 to C2 products on the CuPd(100)interface was 0.61 eV,which was lower than that on Cu(100)(0.72 eV).Encouraged by the DFT calculation results,the CuPd(100)interface catalyst was prepared by a facile chemical solution method and characterized by transmission electron microscopy.CO2 temperature‐programmed desorption and gas sensor experiments further confirmed the enhancement of the CO2 adsorption and CO2*hydrogenation ability of the CuPd(100)interface catalyst.Specifically,the obtained CuPd(100)interface catalyst exhibited a C2 Faradaic efficiency of 50.3%±1.2%at‒1.4 VRHE in 0.1 M KHCO3,which was 2.1 times higher than that of the Cu catalyst(23.6%±1.5%).This study provides the basis for the rational design of Cu‐based electrocatalysts for the generation of multicarbon products by fine‐tuning the intermediate reaction barriers. 展开更多
关键词 Carbon dioxide reduction C2 products ELECTROCATALYST Copper‐palladium interface Intermediate reaction barriers
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Biologically Inspired Design of Context-Aware Smart Products 被引量:5
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作者 ang liu Ivan Teo +4 位作者 Diandi Chen Stephen Lu Thorsten Wuest Zhinan Zhang Fei Tao 《Engineering》 SCIE EI 2019年第4期637-645,共9页
The rapid development of information and communication technologies(ICTs)and cyber-physical systems(CPSs)has paved the way for the increasing popularity of smart products.Context-awareness is an important facet of pro... The rapid development of information and communication technologies(ICTs)and cyber-physical systems(CPSs)has paved the way for the increasing popularity of smart products.Context-awareness is an important facet of product smartness.Unlike artifacts,various bio-systems are naturally characterized by their extraordinary context-awareness.Biologically inspired design(BID)is one of the most commonly employed design strategies.However,few studies have examined the BID of context-aware smart products to date.This paper presents a structured design framework to support the BID of context-aware smart products.The meaning of context-awareness is defined from the perspective of product design.The framework is developed based on the theoretical foundations of the situated function-behavior-structure ontology.A structured design process is prescribed to leverage various biological inspirations in order to support different conceptual design activities,such as problem formulation,structure reformulation,behavior reformulation,and function reformulation.Some existing design methods and emerging design tools are incorporated into the framework.A case study is presented to showcase how this framework can be followed to redesign a robot vacuum cleaner and make it more context-aware. 展开更多
关键词 DESIGN METHOD Biologically inspired DESIGN CONTEXT-AWARENESS INTELLIGENT DESIGN
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Water sorption on coal:effects of oxygen-containing function groups and pore structure 被引量:4
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作者 ang liu Shimin liu +1 位作者 Peng liu Kai Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第5期983-1002,共20页
Coal-water interactions have profound influences on gas extraction from coal and coal utilization.Experimental measurements on three coals using X-ray photoelectron spectroscopy(XPS),low-temperature nitrogen adsorptio... Coal-water interactions have profound influences on gas extraction from coal and coal utilization.Experimental measurements on three coals using X-ray photoelectron spectroscopy(XPS),low-temperature nitrogen adsorption and dynamic water vapor sorption(DVS)were conducted.A mechanism-based isotherm model was proposed to estimate the water vapor uptake at various relative humidities,which is well validated with the DVS data.The validated isotherm model of sorption was further used to derive the isosteric heat of water vapor sorption.The specific surface area of coal pores is not the determining parameter that controls water vapor sorption at least during the primary adsorption stage.Oxidation degree dominates the primary adsorption,and which togethering with the cumulative pore volume determine the secondary adsorption.Higher temperature has limited effects on primary adsorption process.The isosteric heat of water adsorption decreases as water vapor uptake increases,which is found to be close to the latent heat of bulk water condensation at higher relative humidity.The results confirmed that the primary adsorption is controlled by the stronger bonding energy while the interaction energy between water molecules during secondary adsorption stage is relatively weak.However,the thermodynamics of coal-water interactions are complicated since the internal bonding interactions within the coal are disrupted at the same time as new bonding interactions take place within water molecules.Coal has a shrinkage/swelling colloidal structure with moisture loss/gain and it may exhibit collapse behavior with some collapses irreversible as a function of relative humidity,which further plays a significant role in determining moisture retention. 展开更多
关键词 Water vapor ISOTHERM Surface oxidation Pore collapse Isosteric heat of adsorption
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Anisotropic coal permeability and its stress sensitivity 被引量:3
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作者 Zhiming Yan Kai Wang +2 位作者 Jie Zang Chuan Wang ang liu 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第3期507-511,共5页
This paper focuses on anisotropy of coal permeability and its stress sensitivity.Coal blocks were taken from Xinjing Coal Mine in Yangquan Coal District.Coal cores were then drilled along the strike,dip,and vertical d... This paper focuses on anisotropy of coal permeability and its stress sensitivity.Coal blocks were taken from Xinjing Coal Mine in Yangquan Coal District.Coal cores were then drilled along the strike,dip,and vertical directions.Coal permeabilities were measured with respect to stress by using a self-developed coal permeability measurement system.The used samples exhibited significant permeability anisotropy.The permeability along the strike direction was greatest among the three directions,the permeability along the vertical direction was the smallest,and the permeability along the dip direction was between the other two directions.The sensitivity of coal permeability to stress was transversely isotropic.The stress sensitivity coefficient was greater along the horizontal directions than along the vertical directions.Coal permeability exhibited anisotropic stress sensitivity due to anisotropy in Young’s modulus and porosity.The results obtained in this study are useful for optimizing the arrangement of pre-drainage boreholes. 展开更多
关键词 COAL PERMEABILITY ANISOTROPY STRESS sensitivity Gas drainage EXPERIMENT
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Gas metal arc welding of high nitrogen stainless steel with AreN_(2)-O_(2)ternary shielding gas 被引量:2
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作者 Zeng liu Cheng-lei Fan +5 位作者 Zhu Ming Chao Chen ang liu Chun-li Yang San-bao Lin Lang-ping Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第3期923-931,共9页
High nitrogen stainless steel with nitrogen content of 0.75%was welded by gas metal arc welding with Ar-N_(2)-O_(2)ternary shielding gas.The effect of the ternary shielding gas on the retention and improvement of nitr... High nitrogen stainless steel with nitrogen content of 0.75%was welded by gas metal arc welding with Ar-N_(2)-O_(2)ternary shielding gas.The effect of the ternary shielding gas on the retention and improvement of nitrogen content in the weld was identified.Surfacing test was conducted first to compare the ability of O_(2)and CO_(2)in prompting nitrogen dissolution.The nitrogen content of the surfacing metal with O_(2)is slightly higher than CO_(2).And then AreN_(2)-O_(2)shielding gas was applied to weld high nitrogen stainless steel.After using N_(2)-containing shielding gas,the nitrogen content of the weld was improved by 0.1 wt%.As N_(2)continued to increase,the increment of nitrogen content was not obvious,but the ferrite decreased from the top to the bottom.When the proportion of N_(2)reached 20%,a full austenitic weld was obtained and the tensile strength was improved by 8.7%.Combined with the results of surfacing test and welding test,it is concluded that the main effect of N_(2)is to inhibit the escape of nitrogen and suppress the nitrogen diffusion from bottom to the top in the molten pool. 展开更多
关键词 High nitrogen stainless steel AreN2-O2 shielding gas Action mechanism
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A preliminary phylogenetic study of Paraphlomis(Lamiaceae)based on molecular and morphological evidence 被引量:1
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作者 Ya-Ping Chen ang liu +1 位作者 Xun-Lin Yu Chun-Lei Xiang 《Plant Diversity》 SCIE CAS CSCD 2021年第3期206-215,共10页
Paraphlomis is a genus of Lamiaceae with about 30 species distributed mainly in subtropical China.In this study,we carried out the first molecular phylogenetic analyses to elucidate the relationships within the genus ... Paraphlomis is a genus of Lamiaceae with about 30 species distributed mainly in subtropical China.In this study,we carried out the first molecular phylogenetic analyses to elucidate the relationships within the genus based on two nuclear and four plastid DNA regions.Our results,which recovered a species of Matsumurella within Paraphlomis,indicate that the genus is not monophyletic.The two sections and most of the series previously described within the genus are also shown to be polyphyletic.Combining with morphological evidence,our study indicates that nutlet morphology rather than calyx morphology is of phylogenetic value for the infrageneric classification of Paraphlomis.Moreover,P.jiangyongensis,a new species from southern China,is here described,and P.coronata,formerly treated as a variety of P.javanica,is here resurrected as a distinct species within the genus. 展开更多
关键词 Ajugoides Infrageneric classification Matsumurella NUTLET Paraphlomideae
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Quantum-Enhanced Blockchain: A Secure and Practical Blockchain Scheme 被引量:1
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作者 ang liu Xiu-Bo Chen +3 位作者 Gang Xu Zhuo Wang Xuefen Feng Huamin Feng 《Computers, Materials & Continua》 SCIE EI 2023年第7期259-277,共19页
The rapid advancement of quantum technology poses significant security risks to blockchain systems.However,quantum technology can also provide solutions for enhancing blockchain security.In this paper,we propose a qua... The rapid advancement of quantum technology poses significant security risks to blockchain systems.However,quantum technology can also provide solutions for enhancing blockchain security.In this paper,we propose a quantum-enhanced blockchain scheme to achieve a high level of security against quantum computing attacks.We first discuss quantum computing attacks on classic blockchains,including attacks on hash functions,digital signatures,and consensus mechanisms.We then introduce quantum technologies,such as a quantum hash function(QHF),a quantum digital signature(QDS),and proof of authority(PoA)consensus mechanism,into our scheme to improve the security of the blockchain system.Our security analysis demonstrates that our scheme offers superior security against quantum and classic attacks.Finally,we compare our scheme with previous works,showing that our scheme has achieved a perfect balance in terms of practicality,reliability,scalability,and efficiency.Overall,this work contributes to the ongoing research on quantum blockchain in the quantum era. 展开更多
关键词 Quantum blockchain quantum hash function quantum digital signature
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The Wavefront Power Spectral Density Measurement of Aspheric Lens with Long Focal-Length Using a Computer-Generated Hologram 被引量:1
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作者 Xiaohong Wei Kaiyuan Xu ang liu 《Optics and Photonics Journal》 CAS 2022年第11期225-233,共9页
To ensure the performance of the optical system, the machining accuracy of lens with long focal lengths is required to ensure the image quality. A new method for lens transmission wavefront power spectral density (PSD... To ensure the performance of the optical system, the machining accuracy of lens with long focal lengths is required to ensure the image quality. A new method for lens transmission wavefront power spectral density (PSD) in mid-frequency domain measurement using binary phase computer-generated hologram (CGH) is presented. This technique is widely applicable and is particularly useful for measuring large-size lenses with long focal lengths. A comparison experiment of the CGH measurement with results from a Fizeau sphere interferometry method is carried out to verify the accuracy and convenience of the measurement. Furthermore, measurement uncertainty due to CGH fabrication process is analysed. Analysis of the CGH test showed the overall accuracy of less than 1 nm RMS for a sphere lens with over 30 m focal length and Φ410 mm clear aperture. CGH can provide reference spheres with high precision, in the meantime greatly shorten air space, thus reducing the effect of vibration and air turbulence, therefore is of great importance for lens transmission wavefront PSD measurement. The realization of high precision, high efficiency and nondestructive testing of long focal-lens wavefront PSD ensure the ultra-precision and certainty level of machining, hence improving the comprehensive performance of the optical system. 展开更多
关键词 Power Spectral Density Measurement INTERFEROMETRY CGH
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Progress of Geodesy Related Ionosphere from Chinese Scientists in the Period of 2019—2023
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作者 Zishen LI Ningbo Wang +5 位作者 ang liu ang LI Heng Yang Dongshen ZHAO Xiaodong REN Andong HU 《Journal of Geodesy and Geoinformation Science》 CSCD 2023年第3期115-123,共9页
The ionosphere is the ionized part of the upper atmosphere of the Earth,which plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere.It influences radio propagation significan... The ionosphere is the ionized part of the upper atmosphere of the Earth,which plays an important role in atmospheric electricity and forms the inner edge of the magnetosphere.It influences radio propagation significantly,such as the Global Navigation Satellite System(GNSS).Meanwhile,the GNSS is also an essential technique for sensing the variation of ionosphere.During the years of 2019—2023,a large number of Chinese geodesy scientists devoted much efforts to the geodesy related ionosphere.Due to the very limited length,the achievements are carried out from the following six aspects,including:①The ionospheric correction models for BDS and BDSBAS;②Real-time global ionospheric monitoring and modeling;③The ionospheric 2D and 3D modeling based on GNSS and LEO satellites;④The ionospheric prediction based on artificial intelligence;⑤The monitoring and mitigation of ionospheric disturbances for GNSS users;⑥The ionospheric related data products and classical applications. 展开更多
关键词 IONOSPHERE Global Navigation Satellite System(GNSS) BDS satellite-based augmentation system
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Successful surgical resection of large hepatocellular carcinoma with portal vein tumor thrombus after conversion therapy with mFOLFOX-HAIC combined with donafenib and sintilimab:two case reports and a literature review
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作者 Zhitang Guo Ming Zhang +3 位作者 ang liu Zhihong Zhang Kejia Li Jiayun Ge 《Oncology and Translational Medicine》 CAS 2023年第2期66-72,共7页
The aim of our study was to evaluate the clinical efficacy of m FOLFOX-HAIC combined with donafenib and sintilimab conversion therapy followed by surgical resection of large hepatocellular carcinoma with portal vein t... The aim of our study was to evaluate the clinical efficacy of m FOLFOX-HAIC combined with donafenib and sintilimab conversion therapy followed by surgical resection of large hepatocellular carcinoma with portal vein tumor thrombus(PVTT).The clinical data of two patients with large hepatocellular carcinoma who were admitted to the Second Affiliated Hospital of Kunming Medical University were retrospectively collected.Both patients received m FOLFOX-HAIC combined with donafenib and sintilimab conversion therapy,followed by hepatectomy.Clinical data were reported,and clinical efficacy was evaluated.One patient had a 14.5×11.1 cm tumor with a tumor thrombus in the right portal vein.The other patient had a 12.1×8.3 cm tumor with portal and hepatic vein tumor thrombi.Both patients had CNLC stageⅢa prior to conversion therapy,which was reduced to stageⅠb after conversion therapy.Subsequently,the patient underwent open and laparoscopic right hemihepatectomies.Short-term high-intensity conversion therapy with m FOLFOXHAIC combined with donafenib and sintilimab is a feasible and effective treatment for patients with large hepatocellular carcinoma with PVTT. 展开更多
关键词 THROMBUS HEPATOCELLULAR FOLFOX
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The Path Choice and Method of Chinese Rural Governance Ethics Research
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作者 ang liu 《Sociology Study》 2019年第4期169-176,共8页
The 19th National Congress of the Communist Party of China put forward the strategy of Rural Revitalization.Effective governance is the key to rural revitalization.Effective rural governance needs to properly deal wit... The 19th National Congress of the Communist Party of China put forward the strategy of Rural Revitalization.Effective governance is the key to rural revitalization.Effective rural governance needs to properly deal with the ethical relationship in the process of governance.The study of rural governance ethics in China includes three kinds of path choices.They are paradigm shift from top-down to bottom-up,organic integration of special and general,and interweaving between tradition and modernity.The paradigm shift from top-down to bottom-up needs to be done by methods,such as the use of the relationship between theory and practice,the change from abstract research to applied research,and the implementation of fieldwork surveys.Special and general organic integration depends on methods,such as the law of contradiction specificity and universality,the cooperation of induction and deduction,the operation of case studies,etc.The interweaving of tradition and modernity requires methods to be realized,such as the negation of negation,moral narrative,and non-intrusive research. 展开更多
关键词 RURAL GOVERNANCE ETHICS path CHOICE METHOD
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Verification and Improvement of the MTT Method for in vitro HSS Bioactivity Activity Determination
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作者 ang liu Wei Xu 《Journal of Clinical and Nursing Research》 2020年第5期51-55,共5页
To optimize the experimental conditions of MTT colorimetric assay for HSS bioactivity in vitro,we studied the optimal combination of the major conditions of the MTT assay by orthogonal test and other experiments,and c... To optimize the experimental conditions of MTT colorimetric assay for HSS bioactivity in vitro,we studied the optimal combination of the major conditions of the MTT assay by orthogonal test and other experiments,and compared HSS bioactivity in vitro measured by the improved MTT protocol and published MTT assay at serial protein doses.Results showed that the absorbance value(A value)of the MTT assay directly correlated with the number of human hepatoma cell lines SMMC7721.The result of orthogonal test was the number of 5×104 SMMC7721 cells/ml,culture period 6 h before adding HSS,concentration of HSS 100μg/ml,incubation time with HSS 36 h.Additionally,several experiments demonstrated the optimal combination of other conditions was 50μg MTT,incubation time for MTT 6 h,DMSO was used to dissolve the MTT formazan crystals and measured with ELISA scanner at 570 nm.The result of determining HSS bio-activity in vitro by optimized MTT protocol showed that sHSS bio-activity increased with the growth of protein dose,but decreased when it beyond a certain dose.The optimized MTT protocol was a sensitive,convenient and stable quantitative method to evaluate HSS bio-activity. 展开更多
关键词 HSS(Hepatic Stimulator Substance) MTT colorimetric assay Bio-activity
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Secure state estimation for cyber-physical systems with unknown input sliding mode observer
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作者 Panpan Zhang Yuwei Ren +1 位作者 Yixian Fang ang liu 《Control Theory and Technology》 EI CSCD 2024年第2期244-253,共10页
In recent years, cyber attacks have posed great challenges to the development of cyber-physical systems. It is of great significance to study secure state estimation methods to ensure the safe and stable operation of ... In recent years, cyber attacks have posed great challenges to the development of cyber-physical systems. It is of great significance to study secure state estimation methods to ensure the safe and stable operation of the system. This paper proposes a secure state estimation for multi-input and multi-output continuous-time linear cyber-physical systems with sparse actuator and sensor attacks. First, for sparse sensor attacks, we propose an adaptive switching mechanism to mitigate the impact of sparse sensor attacks by filtering out their attack modes. Second, an unknown input sliding mode observer is designed to not only observe the system states, sensor attack signals, and measurement noise present in the system but also counteract the effects of sparse actuator attacks through an unknown input matrix. Finally, for the design of an unknown input sliding mode state observer, the feasibility of the observing system is demonstrated by means of Lyapunov functions. Additionally, simulation experiments are conducted to show the effectiveness of this method. 展开更多
关键词 Sparse attacks Cyber-physical systems Unknown input sliding mode Secure state estimation Adaptive switching mechanism
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桑树内生拮抗菌的分离鉴定及其对桑断枝烂叶病的生防初探 被引量:21
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作者 王若琳 徐伟芳 +4 位作者 王飞 周小磊 郑月 江鸿森 谢洁 《微生物学报》 CAS CSCD 北大核心 2019年第11期2130-2143,共14页
【目的】本研究从健康桑树茎中分离筛选对桑断枝烂叶病菌具显著拮抗作用的内生细菌,为该病生物防治奠定研究基础。【方法】采用组织培养法分离桑树内生菌,抑菌圈法和平板对峙法筛选抑菌活性稳定的内生拮抗菌;根据形态学、生理生化特征... 【目的】本研究从健康桑树茎中分离筛选对桑断枝烂叶病菌具显著拮抗作用的内生细菌,为该病生物防治奠定研究基础。【方法】采用组织培养法分离桑树内生菌,抑菌圈法和平板对峙法筛选抑菌活性稳定的内生拮抗菌;根据形态学、生理生化特征检测和基于16SrDNA、gyrA和gyrB基因的系统发育分析对拮抗菌进行菌种鉴定;利用抑菌圈法测定拮抗菌株活性发酵液热稳定性,菌丝生长速率法检测活性发酵液抑菌谱;并通过观察拮抗菌对桑断枝烂叶病菌BoeremiaexiguaGXH1菌株生长及菌丝形态的影响,扩增抑菌活性物质合成关键基因,以及采用酸沉淀法提取拮抗菌株脂肽类化合物并进行高效液相色谱串联质谱分析(LC-MS),初步探究可能的抑菌机制。【结果】从健康桑树茎中共分离获得17株桑树内生细菌,并从中筛选获得一株对桑断枝烂叶病菌B.exiguaGXH1有稳定拮抗作用的桑树内生细菌NPJ13菌株。该菌株形态学、生理生化特征与芽孢杆菌属一致,基于16SrDNA、gyrA和gyrB基因序列的系统发育分析结果显示该菌株与贝莱斯芽孢杆菌(Bacillusvelezensis)的亲缘关系最近,且处于系统发育树的最小分枝,故将NPJ13菌株鉴定为贝莱斯芽孢杆菌,命名为B.velezensis NPJ13。NPJ13菌株对灰霉病菌SWU5、核地杖菌SXSG-5、核盘菌PZ-2及烟草疫霉SWU20等12种病原真菌具有不同程度的拮抗作用,其活性发酵液具有较好的热稳定性。NPJ13菌株会导致桑断枝烂叶病菌GXH1菌丝发生扭曲、膨大、透明度增加、断裂等畸变现象;基因检测结果显示NPJ13菌株基因组中具有PKSI、NRPS、Sfp、ItuD、Srfc等5种抑菌活性物质合成关键基因,LC-MS检测结果表明菌株NPJ13脂肽类粗提物中含有表面活性素和伊枯草菌素。【结论】本研究分离筛选获得一株对桑断枝烂叶病菌具有显著拮抗作用的桑树内生细菌B.velezensis NPJ13菌株,为桑断枝烂叶病的生物防治提供了候选菌株。 展开更多
关键词 桑树内生菌 拮抗 桑断枝烂叶病 抑菌机理
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一种支持产品平台设计的多准则模块划分方法(英文) 被引量:3
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作者 Wei WEI ang liu +1 位作者 Stephen C.Y.LU Thorsten WUEST 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2015年第1期1-10,共10页
目的:研究多准则约束下的产品模块划分方法,为企业建立稳健的模块化产品平台奠定基础。方法:采用改进的多目标进化算法对建立的多准则模块划分数学模型求解,并采用模糊集合评价机制进行最优解的寻取,得到基于多准则模块划分方法的产品... 目的:研究多准则约束下的产品模块划分方法,为企业建立稳健的模块化产品平台奠定基础。方法:采用改进的多目标进化算法对建立的多准则模块划分数学模型求解,并采用模糊集合评价机制进行最优解的寻取,得到基于多准则模块划分方法的产品模块划分结果。结论:通过改进的多目标进化算法求解多准则模块划分模型,能够得到有效支持产品平台设计的产品模块划分方案。通过与已有优化方法的比较验证了本文提出的多准则模块划分方法的优越性。 展开更多
关键词 模块划分 模块化准则 多目标优化 改进的强度帕累托进化算法 透平膨胀机
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Real-time GNSS precise point positioning with smartphones for vehicle navigation 被引量:3
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作者 Zishen Li Liang Wang +2 位作者 Ningbo Wang Ran Li ang liu 《Satellite Navigation》 2022年第3期140-161,I0004,共23页
The availability of raw Global Navigation Satellite System(GNSS)measurements from Android smart devices gives new possibilities for precise positioning solutions,e.g.,Precise Point Positioning(PPP).However,the accurac... The availability of raw Global Navigation Satellite System(GNSS)measurements from Android smart devices gives new possibilities for precise positioning solutions,e.g.,Precise Point Positioning(PPP).However,the accuracy of the PPP with smart devices currently is a few meters due to the poor quality of the raw GNSS measurements in a kinematic scenario and in urban environments,particularly when the smart devices are placed inside vehicles.To promote the application of GNSS PPP for land vehicle navigation with smart devices,this contribution studies the real-time PPP with smartphones.For data quality analysis and positioning performance validation,two vehicle-based kinematic positioning tests were carried out using two Huawei Mate30 smartphones and two Huawei P40 smartphones with different installation modes:the vehicle-roof mode with smartphones mounted on the top roof outside the vehicle,and the dashboard mode with smartphones stabilized on the dashboard inside the vehicle.To realize high accuracy positioning,we proposed a real-time smartphone PPP method with the data processing strategies adapted for smart devices.Positioning results show that the real-time PPP can achieve the horizontal positioning accuracy of about 1–1.5 m in terms of root-mean-square and better than 2.5 m at the 95th percentile for the vehicle-based kinematic positioning with the experimental smartphones mounted on the dashboard inside the vehicle,which is the real scenario in vehicle navigation. 展开更多
关键词 Global Navigation Satellite System Smartphone positioning Precise point positioning Raw GNSS measurements Land vehicle navigation
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A review of sampling,energy supply and intelligent monitoring for long-term sweat sensors 被引量:2
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作者 Pufan Yang Gaofeng Wei +2 位作者 ang liu Fengwei Huo Zhinan Zhang 《npj Flexible Electronics》 SCIE 2022年第1期308-320,共13页
Sweat is a biofluid with rich information that can reflect an individual’s state of health or activity.But the real-time in situ sweat sensors lack the ability of long-term monitoring.Against this background,this art... Sweat is a biofluid with rich information that can reflect an individual’s state of health or activity.But the real-time in situ sweat sensors lack the ability of long-term monitoring.Against this background,this article provides a holistic review on the necessary process and methods for sweat sensing,including sweat collection,composition analysis,energy supply,and data processing.The impacts of the environment in stimulating sweat production,providing energy supply,and intelligent health monitoring are discussed.Based on the review of previous endeavors,the future development in material,structure and artificial intelligence application of long-term sweat monitoring is envisioned. 展开更多
关键词 artificial INDIVIDUAL processing.
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黄海日照海域部分可培养细菌的分离、初步鉴定及产琼胶酶细菌的筛选 被引量:1
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作者 刘昂 王爽 +2 位作者 杜峰 薛庆节 李秀真 《微生物学报》 CAS CSCD 北大核心 2019年第11期2240-2250,共11页
海洋细菌在海洋的物质与能量循环中起着非常重要的作用。为了适应复杂多变的海洋环境,海洋细菌在物种和基因方面表现出极高的丰富度。【目的】对中国黄海日照海域部分可培养细菌进行分离、初步鉴定,同时筛选产琼胶酶菌株。【方法】对从... 海洋细菌在海洋的物质与能量循环中起着非常重要的作用。为了适应复杂多变的海洋环境,海洋细菌在物种和基因方面表现出极高的丰富度。【目的】对中国黄海日照海域部分可培养细菌进行分离、初步鉴定,同时筛选产琼胶酶菌株。【方法】对从日照海域河流入海口和潮间带沙样和海水中分离到的73株细菌进行了16S rRNA基因序列测定,并进行序列同源性分析。同时检测了这些菌株对琼脂的降解能力。【结果】结果显示,分离到的73株细菌属于4个门、13个科、34个属。18株细菌可能是新分类单元,其中16株为潜在新种,2株为可能的新属。73株细菌中,5株菌具有降解琼脂的能力,最高的琼胶酶活可达到2.17±0.04 U/mL,其中4株嗜琼胶属的细菌降解琼脂糖的产物均为新琼四糖。【结论】本研究丰富了人们对黄海海域可培养细菌多样性的理解,为新物种和新酶的研究提供了基础,并为琼胶酶的提取提供了高产菌株。 展开更多
关键词 可培养细菌 多样性 潜在新种 琼胶酶活性
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