In this paper a method is developed to model the design process gene based on the extensible basic-element with the purpose of design process optimization and reuse. First, the principle of genetic engineering based d...In this paper a method is developed to model the design process gene based on the extensible basic-element with the purpose of design process optimization and reuse. First, the principle of genetic engineering based design process optimization and reuse is put forward and analyzed. Second, the extensible basic-element model of the design process gene is established based on the models of the design process base and the base pair through analyzing the concept and structure of the design process gene and the extensible basic-element as well as its extensibility. Third, the features of divergence and scalability of the extensible basic-element model of the design process gene are discussed for carrying out the extension translation to the design process gene by way of inserting, deleting and updating design process bases. Finally, an example of building extensible basic-element models for the design process base, base pair and design process gene in mechanical product design and the mutation process of the design process gene in airplane design is presented which demonstrates the application of the method proposed in this paper.展开更多
The existing data mining methods are mostly focused on relational databases and structured data, but not on complex structured data (like in extensible markup language(XML)). By converting XML document type descriptio...The existing data mining methods are mostly focused on relational databases and structured data, but not on complex structured data (like in extensible markup language(XML)). By converting XML document type description to the relational semantic recording XML data relations, and using an XML data mining language, the XML data mining system presents a strategy to mine information on XML.展开更多
This paper investigates the existence and uniform decay of global solutions to the initial and boundary value problem with clamped boundary conditions for a nonlinear beam equation with a strong damping.
Active networks are a new kind of packet-switched networks in which packets have code fragments that are executed on the intermediary nodes (routers). The code can extend or modify the foundation architecture of a net...Active networks are a new kind of packet-switched networks in which packets have code fragments that are executed on the intermediary nodes (routers). The code can extend or modify the foundation architecture of a network. In this paper, the authors present a novel active network architecture combined with advantages of two major active networks technology based on extensible services router. The architecture consists of extensible service router, active extensible components server and key distribution center (KDC). Users can write extensible service components with programming interface. At the present time, we have finished the extensible services router prototype system based on Highly Efficient Router Operating System (HEROS), active extensible components server and KDC prototype system based on Linux.展开更多
With the rapid development of network technology, it is increasingly important to dynamically upgrade router’s software. In this paper, the authors present new software architecture to be applied to extensible servic...With the rapid development of network technology, it is increasingly important to dynamically upgrade router’s software. In this paper, the authors present new software architecture to be applied to extensible services router. The novel feature of the architecture is the ability to dynamically load and configure extensible components at run time. Each component implements one function such as packets classification, packets scheduling and routing protocol. We design a simple configuration language (ESRCL) to configure and manage the router. The architecture can be configured according to the packet flows. At present, a prototype system based on highly efficient router operating system (HEROS) has been finished.展开更多
Intellectual capital disclosure (ICD) has experienced a substantial increase in recent decades and many frameworks and guidelines have been issued to provide directions with regard to what constitutes "good" ICD. ...Intellectual capital disclosure (ICD) has experienced a substantial increase in recent decades and many frameworks and guidelines have been issued to provide directions with regard to what constitutes "good" ICD. Companies can use Extensible Business Reporting Language (XBRL) to "build" their own intellectual capital (IC) reports. This digital format has both technical and operating characteristics suitable for reporting non-financial information. This paper reports the findings of a survey of the views of 37 Italian preparers on the scope, the taxonomy, and the assurance of IC reporting via XBRL. It was found that respondents favor the adoption of an IC reporting framework and the standardization of IC indicators. Preferences reveal uncertainty about the level of flexibility for tagging IC information, while supporting the main benefits of XBRL and indicating a marked inclination for tagged information certified by an independent audit. Overall, despite a low awareness of XBRL, the importance placed on standardization of IC information and on the usefulness of the comparability and the speed attribute of XBRL supports the appealing features of this language for developing IC reporting.展开更多
In recent years large corporations as well as smaller commercial enterprises have begun to devote increased attention to software testing and software quality. This paper introduces a novel tool—the Framework for Ext...In recent years large corporations as well as smaller commercial enterprises have begun to devote increased attention to software testing and software quality. This paper introduces a novel tool—the Framework for Extensible Application Testing (FEAT), implemented by the author and applicable for automatic generation and execution of test cases. The paper discusses system requirements, design, architecture and modes of operation. It also contains a detailed comparison of the FEAT framework with existing test environments, focusing in particular on the STAF/STAX framework. The final section is devoted to experimental research into the applicability and efficiency of the presented tools in various projects and configurations, as reflected by quality metrics.展开更多
In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing function vanishing at infi...In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing function vanishing at infinity.Within the theory of process on time-dependent spaces,we investigate the existence of the time-dependent attractor by using the Condition(C_(t))method and more detailed estimates.The results obtained essentially improve and complete some previous works.展开更多
On the basis of formal grammar, this paper introduces operation set θ (e.g.,vector point multiply ·, vector couple multiply * , vector set multiply X, substitution H,function F, set plus ∪, et al.) and set of s...On the basis of formal grammar, this paper introduces operation set θ (e.g.,vector point multiply ·, vector couple multiply * , vector set multiply X, substitution H,function F, set plus ∪, et al.) and set of set' s types L (e.g., ordered set, continuous(descending) ordered set, unordered set, coupled set, coordinate, et al.), and generalizes them toother word types of natural language, thus presenting the generative grammar for words―anextensible 6-element formal system {V_T, V_N, θ, L, S, P}, and takeing time words in naturallanguage as example for detailed discussion. With the colorfulness of time words of naturallanguage, time words for different natural languages assume different meaning. Generative grammarfor time words can generate not only different time words, but also their semantics (Generativegrammar of Chomsky can only produce all right sentences instead of semantics), and then, generalizesthem to other word types, e.g., accurate measure words, adjectives, etc.展开更多
For β∈ R,the authors consider the evolution system in the unknown variables u and ααttu+αxxxxu+αxxtα-(β+αxu L22)αxxu=f,αttα-αxxα-αxxtα-αxxtu=0 describing the dynamics of type III thermoelastic extensi...For β∈ R,the authors consider the evolution system in the unknown variables u and ααttu+αxxxxu+αxxtα-(β+αxu L22)αxxu=f,αttα-αxxα-αxxtα-αxxtu=0 describing the dynamics of type III thermoelastic extensible beams,where the dissipation is entirely contributed by the second equation ruling the evolution of the thermal displacement α.Under natural boundary conditions,the existence of the global attractor of optimal regularity for the related dynamical system acting on the phase space of weak energy solutions is established.展开更多
The martensite start temperature is a critical parameter for steels with metastable austenite.Although numerous models have been developed to predict the martensite start(Ms)temperature,the complexity of the martensit...The martensite start temperature is a critical parameter for steels with metastable austenite.Although numerous models have been developed to predict the martensite start(Ms)temperature,the complexity of the martensitic transformation greatly limits their performance and extensibility.In this work,we apply deep data mining of thermodynamic calculations and deep learning to develop a generic model for Msprediction.Deep data mining was used to establish a hierarchical database with three levels of information.Then,a convolutional neural network model,which can accurately treat the hierarchical data structure,was used to obtain the final model.By integrating thermodynamic calculations,traditional machine learning and deep learning modeling,the final predictor model shows excellent generalizability and extensibility,i.e.model performance both within and beyond the composition range of the original database.The effects of 15 alloying elements were considered successfully using the proposed methodology.The work suggests that,with the help of deep data mining considering the physical mechanisms,deep learning methods can partially mitigate the challenge with limited data in materials science and provide a means for solving complex problems with small databases.展开更多
First-Input-First-Output (FIFO) buffers are extensively used in contemporary digital processors and System-on-Chips (SoC). There are synchronous FIFOs and asycnrhonous FIFOs. And different sized FIFOs should be implem...First-Input-First-Output (FIFO) buffers are extensively used in contemporary digital processors and System-on-Chips (SoC). There are synchronous FIFOs and asycnrhonous FIFOs. And different sized FIFOs should be implemented in different ways. FIFOs are used not only for the pipeline design within a processor, for the inter-processor communication networks, for example Network-on-Chips (NoCs), but also for the peripherals and the clock domain crossing at the whole SoC level. In this paper, we review the interface, the circuit implementation, and the various usages of FIFOs in various levels of the digital design. We can find that the usage of FIFOs could greatly facilitate the signal storage, signal decoupling, signal transfer, power domain separation and power domain crossing in digital systems. We hope that more attentions are paid to the usages of synchronous and asynchronous FIFOs and more sophististicated usages are discovered by the digital design communities.展开更多
A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded direction...A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded direction.The deformation mechanisms responsible for this behaviour were investigated through in-situ electron back-scattered diffraction,grain reference orientation deviation,and slip trace-modified lattice rotation.It was found that anomalous extension twins nucleated mainly at the onset of plastic deformation at or near grain boundary triple junctions.They were associated with the severe strain incompatibility between neighbour grains as a result from the differentbasal slip-induced lattice rotations.Moreover,the anomalous twins were able to grow with the applied strain due to the continuous activation ofbasal slip in different neighbour grains,which enhanced the strain incompatibility.These results reveal the complexity of the deformation mechanisms in Mg alloys at the local level when deformed along hard orientations.展开更多
Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-Apr...Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-April)was studied to reveal the variations of the key factors at different explosive-developing stages.This EC had weak low-level baroclinicity,mid-level cyclonic-vorticity advection,and strong low-level water vapor convergence at the initial explosive-developing stage.The low-level baroclinicity and mid-level cyclonic-vorticity advection increased substantially during the maximum-deepening-rate stage.The diagnostic analyses using the Zwack-Okossi equation showed that diabatic heating was the main contributor to the initial rapid intensification of this EC.The cyclonic-vorticity advection and warm-air advection enhanced rapidly in the middle and upper troposphere and contributed to the maximum rapid intensification,whereas the diabatic heating weakened slightly in the mid-low troposphere.The relative contribution of the diabatic heating decreased from the initial explosive-developing stage to the maximum-deepening-rate stage due to the enhancement of other factors(the cyclonic-vorticity advection and warm-air advection).Furthermore,the physical factors contributing to this EC varied with the explosive-developing stage.The non-key factors at the initial explosive-developing stage need attention to forecast the rapid intensification.展开更多
In this work,anisotropic fatigue crack growth rate(FCGR)behaviour in a hot-rolled Mg-3wt%Al-0.5wt%Ce alloy was investigated using compact tension(CT)specimens with notch(an)parallel to the rolling direction(RD)and tra...In this work,anisotropic fatigue crack growth rate(FCGR)behaviour in a hot-rolled Mg-3wt%Al-0.5wt%Ce alloy was investigated using compact tension(CT)specimens with notch(an)parallel to the rolling direction(RD)and transverse direction(TD).The FCGR tests were conducted at a constant load ratio(R=0.1)and maximum stress intensity factor(KMax=15.6 MPa√m)to investigate the crack closure effect.For both constant R and KMax conditions:(i)the load-displacement curves for every loading cycle were linear for a_(n)∥ to RD and TD,indicating no crack closure;(ii)the FCGR was found to be lower for an∥RD than an∥TD over the entire stress intensity factor range(△K).The hot-rolled sample contained long-aligned Al11Ce3 intermetallic phase within grain boundaries that are elongated along RD.During the FCGR test,{10.12}<10.11>extension twins(ET)with lamellae∼⊥and c-axis∼∥to these elongated intermetallics along RD developed irrespective of the notch orientation.During the loading cycle,these intermetallics along RD generate back-stresses,reducing the in-plane tensile stress∼||and∼⊥to crack-tip to∼0 for a_(n)∥to RD and TD,respectively.Hence,lenticular ET∼||⊥and∼||,with c-axis∼||and∼⊥to crack path activates,leading to trans and inter lamellar crack for anto RD and TD,respectively,and anisotropic FCGR.Translamellar crack in a_(n)∥RD reduces the FCGR due to plastic energy dissipation as perceived by comparatively more geometrically necessary boundaries(GNBs).On the other hand,faster FCGR was obtained for a_(n)∥TD due to interlamellar cracking.Thus,the crack growth through the matrix-ET interfaces was favoured due to strain incompatibility.The Fractography for a_(n)∥RD shows smaller elongated grooves along crack propagation,which indicates crack arrest.However,larger elongated grooves for a_(n)||TD indicated easy crack propagation due to favourable interlamellar crack.展开更多
To explore the effects of freeze‒thaw cycles on the mechanical properties and crack evolution of fissured sandstone,biaxial compression experiments were carried out on sandstone subjected to freeze‒thaw cycles to char...To explore the effects of freeze‒thaw cycles on the mechanical properties and crack evolution of fissured sandstone,biaxial compression experiments were carried out on sandstone subjected to freeze‒thaw cycles to characterize the changes in the physical and mechanical properties of fissured sandstone caused by freeze‒thaw cycles.The crack evolution and crack change process on the surface of the fissured sandstone were recorded and analysed in detail via digital image technology(DIC).Numerical simulation was used to reveal the expansion process and damage mode of fine-scale cracks under the action of freeze‒thaw cycles,and the simulation results were compared and analysed with the experimental data to verify the reliability of the numerical model.The results show that the mass loss,porosity,peak stress and elastic modulus all increase with increasing number of freeze‒thaw cycles.With an increase in the number of freeze‒thaw cycles,a substantial change in displacement occurs around the prefabricated cracks,and a stress concentration appears at the crack tip.As new cracks continue to sprout at the tips of the prefabricated cracks until the microcracks gradually penetrate into the main cracks,the displacement cloud becomes obviously discontinuous,and the contours of the displacement field in the crack fracture damage area simply intersect with the prefabricated cracks to form an obvious fracture.The damage patterns of the fractured sandstone after freeze‒thaw cycles clearly differ,forming a symmetrical"L"-shaped damage pattern at zero freeze‒thaw cycles,a symmetrical"V"-shaped damage pattern at 10 freeze‒thaw cycles,and a"V"-shaped damage pattern at 20 freeze‒thaw cycles.After 20 freeze‒thaw cycles,a"V"-shaped destruction pattern and"L"-shaped destruction pattern are formed;after 30 freeze‒thaw cycles,an"N"-shaped destruction pattern is formed.This shows that the failure mode of fractured sandstone gradually becomes more complicated with an increasing number of freeze‒thaw cycles.The effects of freeze‒thaw cycles on the direction and rate of crack propagation are revealed through a temperature‒load coupled model,which provides an important reference for an in-depth understanding of the freeze‒thaw failure mechanisms of fractured rock masses.展开更多
BACKGROUND Multidrug-resistant Gram-negative bacteria,exacerbated by excessive use of antimicrobials and immunosuppressants,are a major health threat.AIM To study the clinical efficacy and safety of colistin sulfate i...BACKGROUND Multidrug-resistant Gram-negative bacteria,exacerbated by excessive use of antimicrobials and immunosuppressants,are a major health threat.AIM To study the clinical efficacy and safety of colistin sulfate in the treatment of carbapenem-resistant Gram-negative bacilli-induced pneumonia,and to provide theoretical reference for clinical diagnosis and treatment.METHODS This retrospective analysis involved 54 patients with Gram-negative bacilli pneumonia admitted to intensive care unit of The General Hospital of the Northern Theater Command of the People's Liberation Army of China from August 2020 to June 2022.After bacteriological culture,the patients'airway secretions were collected to confirm the presence of Gram-negative bacilli.The patients were divided into the experimental and control groups according to the medication used.The research group consisted of 28 patients who received polymyxin sulfate combined with other drugs through intravenous,nebulization,or intravenous combined with nebulization,with a daily dosage of 1.5–3.0 million units.The control group consisted of 26 patients who received standard dosages of other antibiotics(including sulbactam sodium for injection,cefoperazone sodium sulbactam for injection,tigecycline,meropenem,or vaborbactam).RESULTS Of the 28 patients included in the research group,26 patients showed improvement,treatment was ineffective for two patients,and one patient died,with the treatment efficacy rate of 92.82%.Of the 26 patients in the control group,18 patients improved,treatment was ineffective for eight patients,and two patients died,with the treatment efficacy rate of 54.9%;significant difference was observed between the two groups(P<0.05).The levels of white blood cell(WBC),procalcitonin(PCT),and C-reactive protein(CRP)in both groups were significantly lower after treatment than before treatment(P<0.05),and the levels of WBC,PCT,and CRP in the research group were significantly lower than those in the control group(P<0.05).Compared with before treatment,there were no significant changes in aspartate aminotransferase,creatinine,and glomerular filtration rate in both groups,while total bilirubin and alanine aminotransferase decreased after treatment(P<0.05)with no difference between the groups.In patients with good clinical outcomes,the sequential organ failure assessment(SOFA)score was low when treated with inhaled polymyxin sulfate,and specific antibiotic treatment did not improve the outcome.Sepsis and septic shock as well as a low SOFA score were independent factors associated with good clinical outcomes.CONCLUSION Polymyxin sulfate has a significant effect on the treatment of patients with multiple drug-resistant Gram-negative bacilli pneumonia and other infections in the lungs and is safe and reliable.Moreover,the administration route of low-dose intravenous injection combined with nebulization shows better therapeutic effects and lower adverse reactions,providing new ideas for clinical administration.展开更多
The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still uncertain.New results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ag...The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still uncertain.New results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 Ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.The Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock series.The samples are enriched in HFSEs(i.e.,Ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of Eu.In the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_(N),10000×Al/Ga,Rb/Nb and Nb/Ta etc.,they were proved to be alkaline A-type granite.Combined the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization fractional.The values of ε_(Hf)(t)and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement rocks.The comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate.展开更多
文摘In this paper a method is developed to model the design process gene based on the extensible basic-element with the purpose of design process optimization and reuse. First, the principle of genetic engineering based design process optimization and reuse is put forward and analyzed. Second, the extensible basic-element model of the design process gene is established based on the models of the design process base and the base pair through analyzing the concept and structure of the design process gene and the extensible basic-element as well as its extensibility. Third, the features of divergence and scalability of the extensible basic-element model of the design process gene are discussed for carrying out the extension translation to the design process gene by way of inserting, deleting and updating design process bases. Finally, an example of building extensible basic-element models for the design process base, base pair and design process gene in mechanical product design and the mutation process of the design process gene in airplane design is presented which demonstrates the application of the method proposed in this paper.
文摘The existing data mining methods are mostly focused on relational databases and structured data, but not on complex structured data (like in extensible markup language(XML)). By converting XML document type description to the relational semantic recording XML data relations, and using an XML data mining language, the XML data mining system presents a strategy to mine information on XML.
基金Supported by the NNSF of china(11271066,11326158)Supported by the grant of Shanghai Education Commission(13ZZ048)Supported by the Doctoral Innovational Fund of Donghua University(BC201138)
文摘This paper investigates the existence and uniform decay of global solutions to the initial and boundary value problem with clamped boundary conditions for a nonlinear beam equation with a strong damping.
文摘Active networks are a new kind of packet-switched networks in which packets have code fragments that are executed on the intermediary nodes (routers). The code can extend or modify the foundation architecture of a network. In this paper, the authors present a novel active network architecture combined with advantages of two major active networks technology based on extensible services router. The architecture consists of extensible service router, active extensible components server and key distribution center (KDC). Users can write extensible service components with programming interface. At the present time, we have finished the extensible services router prototype system based on Highly Efficient Router Operating System (HEROS), active extensible components server and KDC prototype system based on Linux.
文摘With the rapid development of network technology, it is increasingly important to dynamically upgrade router’s software. In this paper, the authors present new software architecture to be applied to extensible services router. The novel feature of the architecture is the ability to dynamically load and configure extensible components at run time. Each component implements one function such as packets classification, packets scheduling and routing protocol. We design a simple configuration language (ESRCL) to configure and manage the router. The architecture can be configured according to the packet flows. At present, a prototype system based on highly efficient router operating system (HEROS) has been finished.
文摘Intellectual capital disclosure (ICD) has experienced a substantial increase in recent decades and many frameworks and guidelines have been issued to provide directions with regard to what constitutes "good" ICD. Companies can use Extensible Business Reporting Language (XBRL) to "build" their own intellectual capital (IC) reports. This digital format has both technical and operating characteristics suitable for reporting non-financial information. This paper reports the findings of a survey of the views of 37 Italian preparers on the scope, the taxonomy, and the assurance of IC reporting via XBRL. It was found that respondents favor the adoption of an IC reporting framework and the standardization of IC indicators. Preferences reveal uncertainty about the level of flexibility for tagging IC information, while supporting the main benefits of XBRL and indicating a marked inclination for tagged information certified by an independent audit. Overall, despite a low awareness of XBRL, the importance placed on standardization of IC information and on the usefulness of the comparability and the speed attribute of XBRL supports the appealing features of this language for developing IC reporting.
文摘In recent years large corporations as well as smaller commercial enterprises have begun to devote increased attention to software testing and software quality. This paper introduces a novel tool—the Framework for Extensible Application Testing (FEAT), implemented by the author and applicable for automatic generation and execution of test cases. The paper discusses system requirements, design, architecture and modes of operation. It also contains a detailed comparison of the FEAT framework with existing test environments, focusing in particular on the STAF/STAX framework. The final section is devoted to experimental research into the applicability and efficiency of the presented tools in various projects and configurations, as reflected by quality metrics.
基金National Natural Science Foundation of China(Grant Nos.12101265,12026431,11701230,11731005)Qing Lan Project of Jiangsu Province+1 种基金the dual creative(innovative and entrepreneurial)talents project in Jiangsu Province(Grant No.JSSCBS20210973)China Postdoctoral Science Foundation(Grant No.2022M721392)。
文摘In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing function vanishing at infinity.Within the theory of process on time-dependent spaces,we investigate the existence of the time-dependent attractor by using the Condition(C_(t))method and more detailed estimates.The results obtained essentially improve and complete some previous works.
文摘On the basis of formal grammar, this paper introduces operation set θ (e.g.,vector point multiply ·, vector couple multiply * , vector set multiply X, substitution H,function F, set plus ∪, et al.) and set of set' s types L (e.g., ordered set, continuous(descending) ordered set, unordered set, coupled set, coordinate, et al.), and generalizes them toother word types of natural language, thus presenting the generative grammar for words―anextensible 6-element formal system {V_T, V_N, θ, L, S, P}, and takeing time words in naturallanguage as example for detailed discussion. With the colorfulness of time words of naturallanguage, time words for different natural languages assume different meaning. Generative grammarfor time words can generate not only different time words, but also their semantics (Generativegrammar of Chomsky can only produce all right sentences instead of semantics), and then, generalizesthem to other word types, e.g., accurate measure words, adjectives, etc.
基金supported by the Spanish Ministry of Science and Technology through the Project "Partial Defferential Equations in Thermomechanics.Theory and Applications"(No. MTM2009-08150)
文摘For β∈ R,the authors consider the evolution system in the unknown variables u and ααttu+αxxxxu+αxxtα-(β+αxu L22)αxxu=f,αttα-αxxα-αxxtα-αxxtu=0 describing the dynamics of type III thermoelastic extensible beams,where the dissipation is entirely contributed by the second equation ruling the evolution of the thermal displacement α.Under natural boundary conditions,the existence of the global attractor of optimal regularity for the related dynamical system acting on the phase space of weak energy solutions is established.
基金financially supported by the National Natural Science Foundation of China(Nos.51801019 and U1808208)。
文摘The martensite start temperature is a critical parameter for steels with metastable austenite.Although numerous models have been developed to predict the martensite start(Ms)temperature,the complexity of the martensitic transformation greatly limits their performance and extensibility.In this work,we apply deep data mining of thermodynamic calculations and deep learning to develop a generic model for Msprediction.Deep data mining was used to establish a hierarchical database with three levels of information.Then,a convolutional neural network model,which can accurately treat the hierarchical data structure,was used to obtain the final model.By integrating thermodynamic calculations,traditional machine learning and deep learning modeling,the final predictor model shows excellent generalizability and extensibility,i.e.model performance both within and beyond the composition range of the original database.The effects of 15 alloying elements were considered successfully using the proposed methodology.The work suggests that,with the help of deep data mining considering the physical mechanisms,deep learning methods can partially mitigate the challenge with limited data in materials science and provide a means for solving complex problems with small databases.
文摘First-Input-First-Output (FIFO) buffers are extensively used in contemporary digital processors and System-on-Chips (SoC). There are synchronous FIFOs and asycnrhonous FIFOs. And different sized FIFOs should be implemented in different ways. FIFOs are used not only for the pipeline design within a processor, for the inter-processor communication networks, for example Network-on-Chips (NoCs), but also for the peripherals and the clock domain crossing at the whole SoC level. In this paper, we review the interface, the circuit implementation, and the various usages of FIFOs in various levels of the digital design. We can find that the usage of FIFOs could greatly facilitate the signal storage, signal decoupling, signal transfer, power domain separation and power domain crossing in digital systems. We hope that more attentions are paid to the usages of synchronous and asynchronous FIFOs and more sophististicated usages are discovered by the digital design communities.
基金supported by the project(MAD2DCM)-IMDEA Materials funded by Comunidad de Madrid and by the Recovery,Transformation and Resilience Plan and by NextGenerationEU from the European Union,and by the María de Maeztu seal of excellence from the Spanish Research Agency(CEX2018-000800-M)Mr.B.Yang wishes to express his gratitude for the support of the China Scholarship Council(202106370122).
文摘A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded direction.The deformation mechanisms responsible for this behaviour were investigated through in-situ electron back-scattered diffraction,grain reference orientation deviation,and slip trace-modified lattice rotation.It was found that anomalous extension twins nucleated mainly at the onset of plastic deformation at or near grain boundary triple junctions.They were associated with the severe strain incompatibility between neighbour grains as a result from the differentbasal slip-induced lattice rotations.Moreover,the anomalous twins were able to grow with the applied strain due to the continuous activation ofbasal slip in different neighbour grains,which enhanced the strain incompatibility.These results reveal the complexity of the deformation mechanisms in Mg alloys at the local level when deformed along hard orientations.
基金jointly funded by the State Key Program of the National Natural Science Foundation of China(No.42130605)the Major Program of the National Natural Science Foundation of China(No.72293604)+5 种基金the Youth Innovative Talents Program of Guangdong Colleges and Universities(No.2022KQNCX026)the Natural Science Foundation of Shandong(No.ZR2022MD038)the Project of Enhancing School with Innovation of Guangdong Ocean University(No.230419106)the State Key Program of the National Natural Science Foundation of China(No.42130605)the National Natural Science Foundation of China(Nos.42275001,42276019,42205014,and 42275017)the Guangdong Ocean University Ph.D.Scientific Research Program(No.R19045).
文摘Explosive cyclones(ECs)occur frequently over the Kuroshio/Kuroshio Extension region.The most rapidly intensified EC over the Kuroshio/Kuroshio Extension region during the 42 years(1979-2020)of cold seasons(October-April)was studied to reveal the variations of the key factors at different explosive-developing stages.This EC had weak low-level baroclinicity,mid-level cyclonic-vorticity advection,and strong low-level water vapor convergence at the initial explosive-developing stage.The low-level baroclinicity and mid-level cyclonic-vorticity advection increased substantially during the maximum-deepening-rate stage.The diagnostic analyses using the Zwack-Okossi equation showed that diabatic heating was the main contributor to the initial rapid intensification of this EC.The cyclonic-vorticity advection and warm-air advection enhanced rapidly in the middle and upper troposphere and contributed to the maximum rapid intensification,whereas the diabatic heating weakened slightly in the mid-low troposphere.The relative contribution of the diabatic heating decreased from the initial explosive-developing stage to the maximum-deepening-rate stage due to the enhancement of other factors(the cyclonic-vorticity advection and warm-air advection).Furthermore,the physical factors contributing to this EC varied with the explosive-developing stage.The non-key factors at the initial explosive-developing stage need attention to forecast the rapid intensification.
基金support provided by the Science and Engineering Research Board(Ref.no.:ECR/2016/000125)Department of Science and Technology,Government of India.SB acknowledges the funding by Alexander von Humboldt Foundation,Germany.
文摘In this work,anisotropic fatigue crack growth rate(FCGR)behaviour in a hot-rolled Mg-3wt%Al-0.5wt%Ce alloy was investigated using compact tension(CT)specimens with notch(an)parallel to the rolling direction(RD)and transverse direction(TD).The FCGR tests were conducted at a constant load ratio(R=0.1)and maximum stress intensity factor(KMax=15.6 MPa√m)to investigate the crack closure effect.For both constant R and KMax conditions:(i)the load-displacement curves for every loading cycle were linear for a_(n)∥ to RD and TD,indicating no crack closure;(ii)the FCGR was found to be lower for an∥RD than an∥TD over the entire stress intensity factor range(△K).The hot-rolled sample contained long-aligned Al11Ce3 intermetallic phase within grain boundaries that are elongated along RD.During the FCGR test,{10.12}<10.11>extension twins(ET)with lamellae∼⊥and c-axis∼∥to these elongated intermetallics along RD developed irrespective of the notch orientation.During the loading cycle,these intermetallics along RD generate back-stresses,reducing the in-plane tensile stress∼||and∼⊥to crack-tip to∼0 for a_(n)∥to RD and TD,respectively.Hence,lenticular ET∼||⊥and∼||,with c-axis∼||and∼⊥to crack path activates,leading to trans and inter lamellar crack for anto RD and TD,respectively,and anisotropic FCGR.Translamellar crack in a_(n)∥RD reduces the FCGR due to plastic energy dissipation as perceived by comparatively more geometrically necessary boundaries(GNBs).On the other hand,faster FCGR was obtained for a_(n)∥TD due to interlamellar cracking.Thus,the crack growth through the matrix-ET interfaces was favoured due to strain incompatibility.The Fractography for a_(n)∥RD shows smaller elongated grooves along crack propagation,which indicates crack arrest.However,larger elongated grooves for a_(n)||TD indicated easy crack propagation due to favourable interlamellar crack.
基金supported by the National Natural Science Foundation of China(Project No.52074123).
文摘To explore the effects of freeze‒thaw cycles on the mechanical properties and crack evolution of fissured sandstone,biaxial compression experiments were carried out on sandstone subjected to freeze‒thaw cycles to characterize the changes in the physical and mechanical properties of fissured sandstone caused by freeze‒thaw cycles.The crack evolution and crack change process on the surface of the fissured sandstone were recorded and analysed in detail via digital image technology(DIC).Numerical simulation was used to reveal the expansion process and damage mode of fine-scale cracks under the action of freeze‒thaw cycles,and the simulation results were compared and analysed with the experimental data to verify the reliability of the numerical model.The results show that the mass loss,porosity,peak stress and elastic modulus all increase with increasing number of freeze‒thaw cycles.With an increase in the number of freeze‒thaw cycles,a substantial change in displacement occurs around the prefabricated cracks,and a stress concentration appears at the crack tip.As new cracks continue to sprout at the tips of the prefabricated cracks until the microcracks gradually penetrate into the main cracks,the displacement cloud becomes obviously discontinuous,and the contours of the displacement field in the crack fracture damage area simply intersect with the prefabricated cracks to form an obvious fracture.The damage patterns of the fractured sandstone after freeze‒thaw cycles clearly differ,forming a symmetrical"L"-shaped damage pattern at zero freeze‒thaw cycles,a symmetrical"V"-shaped damage pattern at 10 freeze‒thaw cycles,and a"V"-shaped damage pattern at 20 freeze‒thaw cycles.After 20 freeze‒thaw cycles,a"V"-shaped destruction pattern and"L"-shaped destruction pattern are formed;after 30 freeze‒thaw cycles,an"N"-shaped destruction pattern is formed.This shows that the failure mode of fractured sandstone gradually becomes more complicated with an increasing number of freeze‒thaw cycles.The effects of freeze‒thaw cycles on the direction and rate of crack propagation are revealed through a temperature‒load coupled model,which provides an important reference for an in-depth understanding of the freeze‒thaw failure mechanisms of fractured rock masses.
文摘BACKGROUND Multidrug-resistant Gram-negative bacteria,exacerbated by excessive use of antimicrobials and immunosuppressants,are a major health threat.AIM To study the clinical efficacy and safety of colistin sulfate in the treatment of carbapenem-resistant Gram-negative bacilli-induced pneumonia,and to provide theoretical reference for clinical diagnosis and treatment.METHODS This retrospective analysis involved 54 patients with Gram-negative bacilli pneumonia admitted to intensive care unit of The General Hospital of the Northern Theater Command of the People's Liberation Army of China from August 2020 to June 2022.After bacteriological culture,the patients'airway secretions were collected to confirm the presence of Gram-negative bacilli.The patients were divided into the experimental and control groups according to the medication used.The research group consisted of 28 patients who received polymyxin sulfate combined with other drugs through intravenous,nebulization,or intravenous combined with nebulization,with a daily dosage of 1.5–3.0 million units.The control group consisted of 26 patients who received standard dosages of other antibiotics(including sulbactam sodium for injection,cefoperazone sodium sulbactam for injection,tigecycline,meropenem,or vaborbactam).RESULTS Of the 28 patients included in the research group,26 patients showed improvement,treatment was ineffective for two patients,and one patient died,with the treatment efficacy rate of 92.82%.Of the 26 patients in the control group,18 patients improved,treatment was ineffective for eight patients,and two patients died,with the treatment efficacy rate of 54.9%;significant difference was observed between the two groups(P<0.05).The levels of white blood cell(WBC),procalcitonin(PCT),and C-reactive protein(CRP)in both groups were significantly lower after treatment than before treatment(P<0.05),and the levels of WBC,PCT,and CRP in the research group were significantly lower than those in the control group(P<0.05).Compared with before treatment,there were no significant changes in aspartate aminotransferase,creatinine,and glomerular filtration rate in both groups,while total bilirubin and alanine aminotransferase decreased after treatment(P<0.05)with no difference between the groups.In patients with good clinical outcomes,the sequential organ failure assessment(SOFA)score was low when treated with inhaled polymyxin sulfate,and specific antibiotic treatment did not improve the outcome.Sepsis and septic shock as well as a low SOFA score were independent factors associated with good clinical outcomes.CONCLUSION Polymyxin sulfate has a significant effect on the treatment of patients with multiple drug-resistant Gram-negative bacilli pneumonia and other infections in the lungs and is safe and reliable.Moreover,the administration route of low-dose intravenous injection combined with nebulization shows better therapeutic effects and lower adverse reactions,providing new ideas for clinical administration.
基金granted by Opening Foundation of State Key Laboratory of Continental Dynamics(Grant No.21LCD08),Northwest University。
文摘The magma sources,origins and precise forming ages of the miarolite from Qishan and Kuiqi intrusions are still uncertain.New results reveal that,miarolites from the Qishan and Kuiqi intrusions yield crystallization ages of~101 and~98 Ma,and they have a high formation temperature(~910℃)and low oxygen fugacity value,indicating crystallization condition at low pressure in the upper crust with temperature of 678℃.The Qishan and Kuiqi miarolites are characterized by enrichment in SiO_(2) and high-K alkali,depletion in Ca and Mg,and belong to the high-K weak peraluminous rock series.The samples are enriched in HFSEs(i.e.,Ta,Zr and Hf)and LILEs(i.e.,Ba,P and Sr),depleted in Ba and Sr with the negative anomaly of Eu.In the primitive mantle normalized trace element spider diagram,the samples show a right-inclined‘seagull-type’pattern,combined the ratios of(La/Yb)_(N),10000×Al/Ga,Rb/Nb and Nb/Ta etc.,they were proved to be alkaline A-type granite.Combined the characterize of the trace elements,they were derived from clay-rich source accompanied pelite melting,and subjected to K-feldspar crystallization fractional.The values of ε_(Hf)(t)and tDM2 are distributed in the range of-2.8 to 3.3 with~1.2 Ga,and-6.0 to 4.0 with~1.2 Ga,revealing that they were generated from the Mesoproterozoic Cathaysia basement rocks.The comprehensive research reveals the Kuiqi and Qishan intrusions derived from crust-mantle mixing and partial melting of the crust,respectively,resulting from lithospheric extension generated by the Paleo-Pacific Plate subducted into the European-Asian Plate.