Objective:To obtain fbpB-esxA fusing gene of Mycobacterium tuberculosis(MTU),express the encoded fusing protein in Escherichia coli(E.coli),identify protein acquired,and predict the structure and function of the p...Objective:To obtain fbpB-esxA fusing gene of Mycobacterium tuberculosis(MTU),express the encoded fusing protein in Escherichia coli(E.coli),identify protein acquired,and predict the structure and function of the protein utilizing methods of bioinformatics.Methods:fbpB and esxA gene were amplified from genome of MTB H37Rv by PCR.The fbpB-esxA fusing gene Iigated by(Gly<sub>4</sub>Ser)<sub>3</sub> linker was gained by means of Gene Splicing by Overlapping Extension PCU(SOEPCR), and fusing gene was cloned into expression vector pET-30a.The recombinant plasmid was sequenced and expressed in E.coli BL21(DE3).The protein was identified by Western blot using anti-HIS antibody.Secondary structure and antigenic epitopes of the protein were predicting using tools of bioinformatics.Results:The UNA sequences fbpB-esxA were identical with that published by GenBank.The Ag85B-ESAT-6 fusion protein about 50 kDa comprised 485 amino acids was efficiently produced from expression system in E.coli B1.21(DE3) under the induction of IPTG.Bioinformatics analysis showed the protein contained one transmembrane region and fourteen potential antigenic epitopes.Conclusions:The Ag85B-ESAT-6 fusion protein is successfully expressed with N-terminal HIS-tag.Gel filtration demonstrated that it exists as insoluble inclusion bodies mainly.The existence of linker doesn’t affect immunogenicity of Ag85B and ESAT-6.It will allow lor characterization in vitro and establish a foundation of further function research such as vaccine or diagnostic reagent.展开更多
Satellite rainfall estimate can provide rainfall information over large areas,and raingauge can provide point-based ground observations with high accuracy.With the combination of satellite and raingauge data together,...Satellite rainfall estimate can provide rainfall information over large areas,and raingauge can provide point-based ground observations with high accuracy.With the combination of satellite and raingauge data together,the estimated rainfall fields are greatly improved.This combination method,called 'fusing technique',is discussed in this paper,and the validation for this technique is accomplished with HUBEX IOP data.展开更多
Fan blade off(FBO) from a running turbofan rotor will introduce sudden unbalance into the dynamical system,which will lead to the rub-impact,the asymmetry of rotor and a series of interesting dynamic behavior.The pa...Fan blade off(FBO) from a running turbofan rotor will introduce sudden unbalance into the dynamical system,which will lead to the rub-impact,the asymmetry of rotor and a series of interesting dynamic behavior.The paper first presents a theoretical study on the response excited by sudden unbalance.The results reveal that the reaction force of the bearing located near the fan could always reach a very high value which may lead to the crush of ball,journal sticking,high stress on the other components and some other failures to endanger the safety of engine in FBO event.Therefore,the dynamic influence of a safety design named ‘‘fusing" is investigated by mechanism analysis.Meantime,an explicit FBO model is established to simulate the FBO event,and evaluate the effectiveness and potential dynamic influence of fusing design.The results show that the fusing design could reduce the vibration amplitude of rotor,the reaction force on most bearings and loads on mounts,but the sudden change of support stiffness induced by fusing could produce an impact effect which will couple with the influence of sudden unbalance.Therefore,the implementation of the design should be considered carefully with optimized parameters in actual aero-engine.展开更多
It is well known that deep learning depends on a large amount of clean data.Because of high annotation cost,various methods have been devoted to annotating the data automatically.However,a larger number of the noisy l...It is well known that deep learning depends on a large amount of clean data.Because of high annotation cost,various methods have been devoted to annotating the data automatically.However,a larger number of the noisy labels are generated in the datasets,which is a challenging problem.In this paper,we propose a new method for selecting training data accurately.Specifically,our approach fits a mixture model to the per-sample loss of the raw label and the predicted label,and the mixture model is utilized to dynamically divide the training set into a correctly labeled set,a correctly predicted set,and a wrong set.Then,a network is trained with these sets in the supervised learning manner.Due to the confirmation bias problem,we train the two networks alternately,and each network establishes the data division to teach the other network.When optimizing network parameters,the labels of the samples fuse respectively by the probabilities from the mixture model.Experiments on CIFAR-10,CIFAR-100 and Clothing1M demonstrate that this method is the same or superior to the state-of-the-art methods.展开更多
The low frequency line components of the radiated noise from an underwater target usually have both high spectrum level and sustained stability. This feature could be used to increase the detection performance of conv...The low frequency line components of the radiated noise from an underwater target usually have both high spectrum level and sustained stability. This feature could be used to increase the detection performance of conventional broadband energy integration method. The required spectrum level is theoretically discussed when the detection performance of the known line detection is better than that of broadband energy integration method. Under the condition of the target can be detected in line spectrum band, the relationship between the line spectrum level and signal to noise ratio (SNR) is also discussed. This paper proposes a line spectrum target detection method that a matrix using DC jump to fluctuations ratios of sub-band spatial spectrum and beam space output is constructed. This matrix acts as a filter that the line spectrum target with certain frequency and azimuth is passed at most. By fusing with the other sub band results, the conventional detection performance can be improved. At the same time, the applicable condition and detection performance are analyzed in the paper. The simulation and the sea trial data processing results show that the algorithm can effectively extract weak goal line spectrum target under the condition of multi-interference. The algorithm doesn't need multi-frame statistics and the detection performance is closer to the optimal line spectrum method.展开更多
Replaceable flexural and shear fuse-type coupling beams are used in hybrid coupled shear wall(HCSW)systems,enabling concrete buildings to be promptly recovered after severe earthquakes.This study aimed to analytically...Replaceable flexural and shear fuse-type coupling beams are used in hybrid coupled shear wall(HCSW)systems,enabling concrete buildings to be promptly recovered after severe earthquakes.This study aimed to analytically evaluate the seismic behavior of flexural and shear fuse beams situated in short-,medium-and high-rise RC buildings that have HCSWs.Three building groups hypothetically located in a high seismic hazard zone were studied.A series of 2D nonlinear time history analyses was accomplished in OpenSees,using the ground motion records scaled at the design basis earthquake level.It was found that the effectiveness of fuses in HCSWs depends on various factors such as size and scale of the building,allowable rotation value,inter-story drift ratio,residual drift quantity,energy dissipation value of the fuses,etc.The results show that shear fuses better meet the requirements of rotations and drifts.In contrast,flexural fuses dissipate more energy,but their sectional stiffness should increase to meet other requirements.It was concluded that adoption of proper fuses depends on the overall scale of the building and on how associated factors are considered.展开更多
A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage sites.The proposed model extracts the resi...A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage sites.The proposed model extracts the residual strain from the differences in thermoelastic contraction of fused silica with different fictive temperatures from the initial frozen-in temperatures to ambient temperature.The residual stress fields of mitigated damage sites for the CO_(2)laser-annealed case are obtained by a finite element analysis of equilibrium equations and constitutive equations.The simulated results indicate that the proposed model can accurately evaluate the residual stress fields of laser-annealed mitigated damage sites with a complex thermal history.The calculated maximum hoop stress is in good agreement with the reported experimental result.The estimated optical retardance profiles from the calculated radial and hoop stress fields are consistent with the photoelastic measurements.These results provide sufficient evidence to demonstrate the suitability of the proposed model for describing the residual stresses of mitigated fused silica damage sites after CO_(2)laser annealing.展开更多
From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open chains.Although the category of aromatic energetic compounds exh...From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open chains.Although the category of aromatic energetic compounds exhibits several advantages in the regulation of energetic properties,the nonaromatic heterocycles,assembling nitramino explosophores with simple alkyl bridges,still have prevailed in benchmark materials.The methylene bridge plays a pivotal role in the constructions of the classic nonaromatic heterocycle-based energetic compounds,e.g.,hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX)and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),whereas ethylene bridge is the core moiety of state-of-the-art explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20).In this context,it is of great interest to employ simple and practical bridges to assemble aromatic and nonaromatic nitrogen-rich heterocycles,thereby expanding the structural diversity of energetic materials,e.g.,bridged and fused nitrogen-rich poly-heterocycles.Furthermore,alkyl-bridged poly-heterocycles highlight the potential for the open chain type of energetic materials.In this review,the development of alkyl bridges in linking nitrogen-rich heterocycles is presented,and the perspective of the newly constructed energetic backbones is summarized for the future design of advanced energetic materials.展开更多
The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction ...The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse actuator.The impact point easily deviates from the target,and thus the correction result cannot be readily evaluated.However,the cost of shooting tests is considerably high to conduct many tests for data collection.To address this issue,this study proposes an aiming method for shooting tests based on small sample size.The proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion center.The experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future.展开更多
Introduction: Coccydynia, television disease, and coccygodynia are the different names given to this disabling disease, which can become chronic. It was described by Simson in 1859. Coccydynia means pain at the end of...Introduction: Coccydynia, television disease, and coccygodynia are the different names given to this disabling disease, which can become chronic. It was described by Simson in 1859. Coccydynia means pain at the end of the vertebral column. Non-traumatic coccydynia is a diagnosis, which is never straightforward like traumatic coccydynia because the onset is unclear, and both the patient and the unaware clinician face many challenges in treating it on time and with accuracy. Coccyx was likened to a cuckoo bird’s beak as a curved bone of fused 3 to 5 vertebrae with remnant disc material in some rare cases, unfused segments, linear scoliosis or subluxations and deformities. Stress X-rays of the coccyx in the antero-posterior and lateral views in standing and sitting reveal the “Dynamic Instability” due to congenital coccygeal morphological, pathological and mechanical variations. Material and Methods: This is a complex study having retrograde data collected from online publications from various databases, like PubMed, Embase, and Cochrane Library and also antegrade data collected from 100 patients with their consent from patients in Adam and Eve Specialised Medical Centre-based at Abu Dhabi, UAE and data was processed in the research centre of Krushi Orthopaedic Welfare Society based in India between 2014-2024 following all guidelines of Helsinki and approved by the ethics board of Krushi Orthopaedic Welfare Society. Clinical Presentation: The coccyx is painful, with aches, spasms, and an inability to sit. This affects daily activities without any particular date of onset. The onset remains insidious for the non-traumatic variety of coccydynia. Aetiology and Patho Anatomy: Non-traumatic coccydynia can be caused by a myriad of reasons, like congenital morphological variations, acquired dynamic instabilities, and hidden trauma remaining quiescent to re-surface as a strain-induced pain. Radiological Presentations: Unless clarity is focused on these coccygeal views, the errors of the unevacuated rectum, non-dynamic standing views, improper X-ray exposure and refuge by insurance companies to approve the much needed but multiple views in radiological investigation (Stress X-ray), MRI scan, lack of awareness by the clinician, all lead to missed diagnosis with its repercussions as congenital variations in morphology, acquired changes in structure/mobility, pathologies like tumours like congenital teratoma & adult onset chordoma, Tarlov cysts, pilonidal sinus or infections—even tuberculosis, dural syndrome, stiff coccyx due to ankylosing spondylitis and many others like relation to neurosis have all been documented. Treatment options are outside the scope of this research topic, as only the differential diagnosis is being stressed here, so that the clinician and the patient do not overlook the varying aetiology, which is the first step to timely and appropriate treatment. Conclusion: Level 3 evidence is available pointing towards many aetiologies causing non-traumatic coccydynia, and in this study of 100 patients by Krushi O W S, a non-profit organisation, the results were as follows: 1) Coccydynia is more common in Type II coccyx and bony spicules. 2) Coccydynia is more prevalent when the sacrococcygeal joints are not fused. 3) Coccydynia is more prevalent when there is subluxation at the intercoccygeal joints. 4) Coccydynia is more when the sacral angle is lower. 5) Coccydynia is associated with higher sacrococcygeal curved length. 6) Coccydynia is associated with a lower sacrococcygeal curvature index. 7) Gender variations: The coccygeal curvature index was lower in females with coccydynia;the intercoccygeal angle was lower in males. 8) Both obese and thin individuals can get affected due to different weight-bearing mechanics in play.展开更多
Considering that almost all existing solutions of fusing different reconstructed results require experts’opinions and the issue of how to fuse probabilistic results and mixed results has not been discussed.Two soluti...Considering that almost all existing solutions of fusing different reconstructed results require experts’opinions and the issue of how to fuse probabilistic results and mixed results has not been discussed.Two solutions are proposed.The first is based on the Monte Carlo Method(FMCM),while the second is based on the Sub-Interval Technique(FSIT).The method based on FMCM generates sample points according to the distribution of each uncertain result firstly,and then gives out the cumulative distribution function of the final fused result by statistical analysis.The method based on FSIT gets the result fusion interval set according to lower and upper bounds of all interval results and a given length d of each sub-interval firstly,and then calculate the weighted matrix of the result fusion interval.As a result,the cumulative distribution function of the final fused result can also be given out by statistical analysis.Finally,three real accidents are given to demonstrate the methods of FMCM and FSIT,the results of which show that both work well in practice.展开更多
Mutations in presenilin 1(PS1)gene are closely associated with the early onset of familial Alzheimer’s disease(EOFAD).The fusion genes,GFP-PS1(recombinant plasmid pEGFP-C1-PS1)and PS1-GFP(recombinant plasmid pEGFP-N2...Mutations in presenilin 1(PS1)gene are closely associated with the early onset of familial Alzheimer’s disease(EOFAD).The fusion genes,GFP-PS1(recombinant plasmid pEGFP-C1-PS1)and PS1-GFP(recombinant plasmid pEGFP-N2-PS1)were constructed to study the subcellular localization of PS1 holoprotein.Recombinant plasmids were transiently transfected into two cell lines,HEK293 and CHO,respectively,using the green fluorescence from GFP(green fluorescence protein)as the PS1 localization signal.Then,we observed green fluorescence with a SPOT II(Olympus,BH2)and CONFOCAL microscope(Olympus,FV300)under 488 nm.The results show that PS1 located on the nuclear envelope.A few can be found on the cellular membrane and in the cytosol in a non-homogeneous distribution.展开更多
Diseases of the blood system are highly complicated and involve many aspects.This article aimed to put forward the necessity of integrating quality and professional education,the necessity of learning logic,and the im...Diseases of the blood system are highly complicated and involve many aspects.This article aimed to put forward the necessity of integrating quality and professional education,the necessity of learning logic,and the importance of establishing an integrated medical education model when teaching about blood system diseases.According to the requirements of the new medical science,this article puts forward the integration of an“online+offline+clinical”medical education mode based on the social learning theory and a learning evaluation mode based on medical literacy.The fundamental task of cultivating human beings into clinical medical talents with professional ethics,independent learning abilities,interpersonal communication abilities,complex problem-solving abilities,innovative consciousness,and critical thinking was implemented.This article aims to propose an improved construction plan to create a new and improved teaching system in medicine.展开更多
The general use of aluminium as an indentation standard for the iteration of contact heights for the determination of ISO-14577 hardness and elastic modulus is challenged because of as yet not appreciated phase-change...The general use of aluminium as an indentation standard for the iteration of contact heights for the determination of ISO-14577 hardness and elastic modulus is challenged because of as yet not appreciated phase-changes in the physical force-depth standard curve that seemed to be secured by claims from 1992. The physical and mathematical analyses with closed formulas avoid the still world-wide standardized energy-law violation by not reserving 33.33% (h2 belief) (or 20% h3/2 physical law) of the loading force and thus energy for all not depth producing events but using 100% for the depth formation is a severe violation of the energy law. The not depth producing part of the indentation work cannot be done with zero energy! Both twinning and structural phase-transition onsets and normalized phase-transition energies are now calculated without iterations but with physically correct closed arithmetic equations. These are reported for Berkovich and cubecorner indentations, including their comparison on geometric grounds and an indentation standard without mechanical twinning is proposed. Characteristic data are reported. This is the first detection of the indentation twinning of aluminium at room temperature and the mechanical twinning of fused quartz is also new. Their disqualification as indentation standards is established. Also, the again found higher load phase-transitions disqualify aluminium and fused quartz as ISO-ASTM 14577 (International Standardization Organization and American Society for Testing and Materials) standards for the contact depth “hc” iterations. The incorrect and still world-wide used black-box values for H- and Er-values (the latter are still falsely called “Young’s moduli” even though they are not directional) and all mechanical properties that depend on them. They lack relation to bulk moduli from compression experiments. Experimentally obtained and so published force vs depth parabolas always follow the linear FN = kh3/2 + Fa equation, where Fa is the axis-cut before and after the phase-transition branches (never “h2” as falsely enforced and used for H, Er and giving incorrectly calculated parameters). The regression slopes k are the precise physical hardness values, which for the first time allow for precise calculation of the mechanical qualities by indentation in relation to the geometry of the indenter tip. Exactly 20% of the applied force and thus energy is not available for the indentation depth. Only these scientific k-values must be used for AI-advises at the expense of falsely iterated indentation hardness H-values. Any incorrect H-ISO-ASTM and also the iterated Er-ISO-ASTM modulus values of technical materials in artificial intelligence will be a disaster for the daily safety. The AI must be told that these are unscientific and must therefore be replaced by physical data. Iterated data (3 and 8 free parameters!) cannot be transformed into physical data. One has to start with real experimental loading curves and an absolute ZerodurR standard that must be calibrated with standard force and standard length to create absolute indentation results. .展开更多
Additive manufacturing(AM)is a free-form technology that shows great potential in the integrated creation of three-dimensional(3D)electronics.However,the fabrication of 3D conformal circuits that fulfill the requireme...Additive manufacturing(AM)is a free-form technology that shows great potential in the integrated creation of three-dimensional(3D)electronics.However,the fabrication of 3D conformal circuits that fulfill the requirements of high service temperature,high conductivity and high resolution remains a challenge.In this paper,a hybrid AM method combining the fused deposition modeling(FDM)and hydrophobic treatment assisted laser activation metallization(LAM)was proposed for manufacturing the polyetheretherketone(PEEK)-based 3D electronics,by which the conformal copper patterns were deposited on the 3D-printed PEEK parts,and the adhesion between them reached the 5B high level.Moreover,the 3D components could support the thermal cycling test from-55℃ to 125℃ for more than 100 cycles.Particularly,the application of a hydrophobic coating on the FDM-printed PEEK before LAM can promote an ideal catalytic selectivity on its surface,not affected by the inevitable printing borders and pores in the FDM-printed parts,then making the resolution of the electroless plated copper lines improved significantly.In consequence,Cu lines with width and spacing of only60μm and 100μm were obtained on both as-printed and after-polished PEEK substrates.Finally,the potential of this technique to fabricate 3D conformal electronics was demonstrated.展开更多
Ideal tissue engineering scaffolds need interconnected pores and high porosity to enable cell survival,migration,proliferation,and differentiation.However,obtaining a high-resolution structure is difficult with tradit...Ideal tissue engineering scaffolds need interconnected pores and high porosity to enable cell survival,migration,proliferation,and differentiation.However,obtaining a high-resolution structure is difficult with traditional one-temperature control fused deposition modeling(FDM).In this study,we propose a dual-temperature control method to improve printability.A numerical model is developed in which the viscosity is a function of temperature and shear rate to study the influence of two different temperature control modes.Quantitative tests are used to assess filament formation and shape fidelity,including one-dimensional filament printing,deposition at corners,fusion,and collapse.By using dual-temperature control,the width of the deposited poly(ε-caprolactone)filament is reduced to 50μm.The comparative results of both the experimental method and numerical simulation suggest that the dual-temperature control FDM can manufacture spatially arranged constructs and presents a promising application in tissue engineering。展开更多
The urgent need to develop customized functional products only possible by 3D printing had realized when faced with the unavailability of medical devices like surgical instruments during the coronavirus-19 disease and...The urgent need to develop customized functional products only possible by 3D printing had realized when faced with the unavailability of medical devices like surgical instruments during the coronavirus-19 disease and the ondemand necessity to perform surgery during space missions.Biopolymers have recently been the most appropriate option for fabricating surgical instruments via 3D printing in terms of cheaper and faster processing.Among all 3D printing techniques,fused deposition modelling(FDM)is a low-cost and more rapid printing technique.This article proposes the fabrication of surgical instruments,namely,forceps and hemostat using the fused deposition modeling(FDM)process.Excellent mechanical properties are the only indicator to judge the quality of the functional parts.The mechanical properties of FDM-processed parts depend on various process parameters.These parameters are layer height,infill pattern,top/bottom pattern,number of top/bottom layers,infill density,flow,number of shells,printing temperature,build plate temperature,printing speed,and fan speed.Tensile strength and modulus of elasticity are chosen as evaluation indexes to ascertain the mechanical properties of polylactic acid(PLA)parts printed by FDM.The experiments have performed through Taguchi’s L27orthogonal array(OA).Variance analysis(ANOVA)ascertains the significance of the process parameters and their percent contributions to the evaluation indexes.Finally,as a multiobjective optimization technique,grey relational analysis(GRA)obtains an optimal set of FDM process parameters to fabricate the best parts with comprehensive mechanical properties.Scanning electron microscopy(SEM)examines the types of defects and strong bonding between rasters.The proposed research ensures the successful fabrication of functional surgical tools with substantial ultimate tensile strength(42.6 MPa)and modulus of elasticity(3274 MPa).展开更多
基金Supported by Research Program of The Health Department of Hainan Province(No.2007-44)Research Cultivation Program of Hainan Medical University(HY2010-006)+1 种基金Research Program in higher educational institutes of The Education Department of Hainan Province(No.Hj2010-21)Natural Science Fund of Hainan Province(No.2008~30837)
文摘Objective:To obtain fbpB-esxA fusing gene of Mycobacterium tuberculosis(MTU),express the encoded fusing protein in Escherichia coli(E.coli),identify protein acquired,and predict the structure and function of the protein utilizing methods of bioinformatics.Methods:fbpB and esxA gene were amplified from genome of MTB H37Rv by PCR.The fbpB-esxA fusing gene Iigated by(Gly<sub>4</sub>Ser)<sub>3</sub> linker was gained by means of Gene Splicing by Overlapping Extension PCU(SOEPCR), and fusing gene was cloned into expression vector pET-30a.The recombinant plasmid was sequenced and expressed in E.coli BL21(DE3).The protein was identified by Western blot using anti-HIS antibody.Secondary structure and antigenic epitopes of the protein were predicting using tools of bioinformatics.Results:The UNA sequences fbpB-esxA were identical with that published by GenBank.The Ag85B-ESAT-6 fusion protein about 50 kDa comprised 485 amino acids was efficiently produced from expression system in E.coli B1.21(DE3) under the induction of IPTG.Bioinformatics analysis showed the protein contained one transmembrane region and fourteen potential antigenic epitopes.Conclusions:The Ag85B-ESAT-6 fusion protein is successfully expressed with N-terminal HIS-tag.Gel filtration demonstrated that it exists as insoluble inclusion bodies mainly.The existence of linker doesn’t affect immunogenicity of Ag85B and ESAT-6.It will allow lor characterization in vitro and establish a foundation of further function research such as vaccine or diagnostic reagent.
基金supported by National Basic Research Projects (No.2000048703 and 2001CB309402)
文摘Satellite rainfall estimate can provide rainfall information over large areas,and raingauge can provide point-based ground observations with high accuracy.With the combination of satellite and raingauge data together,the estimated rainfall fields are greatly improved.This combination method,called 'fusing technique',is discussed in this paper,and the validation for this technique is accomplished with HUBEX IOP data.
基金the financial support from the National Natural Science Foundation of China(Nos.51575022 and 51475021)
文摘Fan blade off(FBO) from a running turbofan rotor will introduce sudden unbalance into the dynamical system,which will lead to the rub-impact,the asymmetry of rotor and a series of interesting dynamic behavior.The paper first presents a theoretical study on the response excited by sudden unbalance.The results reveal that the reaction force of the bearing located near the fan could always reach a very high value which may lead to the crush of ball,journal sticking,high stress on the other components and some other failures to endanger the safety of engine in FBO event.Therefore,the dynamic influence of a safety design named ‘‘fusing" is investigated by mechanism analysis.Meantime,an explicit FBO model is established to simulate the FBO event,and evaluate the effectiveness and potential dynamic influence of fusing design.The results show that the fusing design could reduce the vibration amplitude of rotor,the reaction force on most bearings and loads on mounts,but the sudden change of support stiffness induced by fusing could produce an impact effect which will couple with the influence of sudden unbalance.Therefore,the implementation of the design should be considered carefully with optimized parameters in actual aero-engine.
基金supported by SRC-Open Project of Research Center of Security Video and Image Processing Engineering Technology of Guizhou ([2020]001)Beijing Advanced Innovation Center for Intelligent Robots and Systems (2018IRS20)National Natural Science Foundation of China (Grant No.61973334).
文摘It is well known that deep learning depends on a large amount of clean data.Because of high annotation cost,various methods have been devoted to annotating the data automatically.However,a larger number of the noisy labels are generated in the datasets,which is a challenging problem.In this paper,we propose a new method for selecting training data accurately.Specifically,our approach fits a mixture model to the per-sample loss of the raw label and the predicted label,and the mixture model is utilized to dynamically divide the training set into a correctly labeled set,a correctly predicted set,and a wrong set.Then,a network is trained with these sets in the supervised learning manner.Due to the confirmation bias problem,we train the two networks alternately,and each network establishes the data division to teach the other network.When optimizing network parameters,the labels of the samples fuse respectively by the probabilities from the mixture model.Experiments on CIFAR-10,CIFAR-100 and Clothing1M demonstrate that this method is the same or superior to the state-of-the-art methods.
文摘The low frequency line components of the radiated noise from an underwater target usually have both high spectrum level and sustained stability. This feature could be used to increase the detection performance of conventional broadband energy integration method. The required spectrum level is theoretically discussed when the detection performance of the known line detection is better than that of broadband energy integration method. Under the condition of the target can be detected in line spectrum band, the relationship between the line spectrum level and signal to noise ratio (SNR) is also discussed. This paper proposes a line spectrum target detection method that a matrix using DC jump to fluctuations ratios of sub-band spatial spectrum and beam space output is constructed. This matrix acts as a filter that the line spectrum target with certain frequency and azimuth is passed at most. By fusing with the other sub band results, the conventional detection performance can be improved. At the same time, the applicable condition and detection performance are analyzed in the paper. The simulation and the sea trial data processing results show that the algorithm can effectively extract weak goal line spectrum target under the condition of multi-interference. The algorithm doesn't need multi-frame statistics and the detection performance is closer to the optimal line spectrum method.
文摘Replaceable flexural and shear fuse-type coupling beams are used in hybrid coupled shear wall(HCSW)systems,enabling concrete buildings to be promptly recovered after severe earthquakes.This study aimed to analytically evaluate the seismic behavior of flexural and shear fuse beams situated in short-,medium-and high-rise RC buildings that have HCSWs.Three building groups hypothetically located in a high seismic hazard zone were studied.A series of 2D nonlinear time history analyses was accomplished in OpenSees,using the ground motion records scaled at the design basis earthquake level.It was found that the effectiveness of fuses in HCSWs depends on various factors such as size and scale of the building,allowable rotation value,inter-story drift ratio,residual drift quantity,energy dissipation value of the fuses,etc.The results show that shear fuses better meet the requirements of rotations and drifts.In contrast,flexural fuses dissipate more energy,but their sectional stiffness should increase to meet other requirements.It was concluded that adoption of proper fuses depends on the overall scale of the building and on how associated factors are considered.
基金Project supported by the National Natural Science Foundation of China(Grant No.62275235).
文摘A numerical model based on measured fictive temperature distributions is explored to evaluate the residual stress fields of CO_(2)laser-annealed mitigated fused silica damage sites.The proposed model extracts the residual strain from the differences in thermoelastic contraction of fused silica with different fictive temperatures from the initial frozen-in temperatures to ambient temperature.The residual stress fields of mitigated damage sites for the CO_(2)laser-annealed case are obtained by a finite element analysis of equilibrium equations and constitutive equations.The simulated results indicate that the proposed model can accurately evaluate the residual stress fields of laser-annealed mitigated damage sites with a complex thermal history.The calculated maximum hoop stress is in good agreement with the reported experimental result.The estimated optical retardance profiles from the calculated radial and hoop stress fields are consistent with the photoelastic measurements.These results provide sufficient evidence to demonstrate the suitability of the proposed model for describing the residual stresses of mitigated fused silica damage sites after CO_(2)laser annealing.
基金National Natural Science Foundation of China(Grant Nos.22075023,22205022,and 22235003)to provide fund for conducting experiments。
文摘From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open chains.Although the category of aromatic energetic compounds exhibits several advantages in the regulation of energetic properties,the nonaromatic heterocycles,assembling nitramino explosophores with simple alkyl bridges,still have prevailed in benchmark materials.The methylene bridge plays a pivotal role in the constructions of the classic nonaromatic heterocycle-based energetic compounds,e.g.,hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX)and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),whereas ethylene bridge is the core moiety of state-of-the-art explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20).In this context,it is of great interest to employ simple and practical bridges to assemble aromatic and nonaromatic nitrogen-rich heterocycles,thereby expanding the structural diversity of energetic materials,e.g.,bridged and fused nitrogen-rich poly-heterocycles.Furthermore,alkyl-bridged poly-heterocycles highlight the potential for the open chain type of energetic materials.In this review,the development of alkyl bridges in linking nitrogen-rich heterocycles is presented,and the perspective of the newly constructed energetic backbones is summarized for the future design of advanced energetic materials.
基金the National Natural Science Foundation of China(Grant No.61973033)Preliminary Research of Equipment(Grant No.9090102010305)for funding the experiments。
文摘The longitudinal dispersion of the projectile in shooting tests of two-dimensional trajectory corrections fused with fixed canards is extremely large that it sometimes exceeds the correction ability of the correction fuse actuator.The impact point easily deviates from the target,and thus the correction result cannot be readily evaluated.However,the cost of shooting tests is considerably high to conduct many tests for data collection.To address this issue,this study proposes an aiming method for shooting tests based on small sample size.The proposed method uses the Bootstrap method to expand the test data;repeatedly iterates and corrects the position of the simulated theoretical impact points through an improved compatibility test method;and dynamically adjusts the weight of the prior distribution of simulation results based on Kullback-Leibler divergence,which to some extent avoids the real data being"submerged"by the simulation data and achieves the fusion Bayesian estimation of the dispersion center.The experimental results show that when the simulation accuracy is sufficiently high,the proposed method yields a smaller mean-square deviation in estimating the dispersion center and higher shooting accuracy than those of the three comparison methods,which is more conducive to reflecting the effect of the control algorithm and facilitating test personnel to iterate their proposed structures and algorithms.;in addition,this study provides a knowledge base for further comprehensive studies in the future.
文摘Introduction: Coccydynia, television disease, and coccygodynia are the different names given to this disabling disease, which can become chronic. It was described by Simson in 1859. Coccydynia means pain at the end of the vertebral column. Non-traumatic coccydynia is a diagnosis, which is never straightforward like traumatic coccydynia because the onset is unclear, and both the patient and the unaware clinician face many challenges in treating it on time and with accuracy. Coccyx was likened to a cuckoo bird’s beak as a curved bone of fused 3 to 5 vertebrae with remnant disc material in some rare cases, unfused segments, linear scoliosis or subluxations and deformities. Stress X-rays of the coccyx in the antero-posterior and lateral views in standing and sitting reveal the “Dynamic Instability” due to congenital coccygeal morphological, pathological and mechanical variations. Material and Methods: This is a complex study having retrograde data collected from online publications from various databases, like PubMed, Embase, and Cochrane Library and also antegrade data collected from 100 patients with their consent from patients in Adam and Eve Specialised Medical Centre-based at Abu Dhabi, UAE and data was processed in the research centre of Krushi Orthopaedic Welfare Society based in India between 2014-2024 following all guidelines of Helsinki and approved by the ethics board of Krushi Orthopaedic Welfare Society. Clinical Presentation: The coccyx is painful, with aches, spasms, and an inability to sit. This affects daily activities without any particular date of onset. The onset remains insidious for the non-traumatic variety of coccydynia. Aetiology and Patho Anatomy: Non-traumatic coccydynia can be caused by a myriad of reasons, like congenital morphological variations, acquired dynamic instabilities, and hidden trauma remaining quiescent to re-surface as a strain-induced pain. Radiological Presentations: Unless clarity is focused on these coccygeal views, the errors of the unevacuated rectum, non-dynamic standing views, improper X-ray exposure and refuge by insurance companies to approve the much needed but multiple views in radiological investigation (Stress X-ray), MRI scan, lack of awareness by the clinician, all lead to missed diagnosis with its repercussions as congenital variations in morphology, acquired changes in structure/mobility, pathologies like tumours like congenital teratoma & adult onset chordoma, Tarlov cysts, pilonidal sinus or infections—even tuberculosis, dural syndrome, stiff coccyx due to ankylosing spondylitis and many others like relation to neurosis have all been documented. Treatment options are outside the scope of this research topic, as only the differential diagnosis is being stressed here, so that the clinician and the patient do not overlook the varying aetiology, which is the first step to timely and appropriate treatment. Conclusion: Level 3 evidence is available pointing towards many aetiologies causing non-traumatic coccydynia, and in this study of 100 patients by Krushi O W S, a non-profit organisation, the results were as follows: 1) Coccydynia is more common in Type II coccyx and bony spicules. 2) Coccydynia is more prevalent when the sacrococcygeal joints are not fused. 3) Coccydynia is more prevalent when there is subluxation at the intercoccygeal joints. 4) Coccydynia is more when the sacral angle is lower. 5) Coccydynia is associated with higher sacrococcygeal curved length. 6) Coccydynia is associated with a lower sacrococcygeal curvature index. 7) Gender variations: The coccygeal curvature index was lower in females with coccydynia;the intercoccygeal angle was lower in males. 8) Both obese and thin individuals can get affected due to different weight-bearing mechanics in play.
基金This work was supported by the National Natural Science Foundation of China[grant number 51775056]the Natural Science Foundation of Hunan Province[grant number 2018JJ3544]the Hunan Provincial Innovation Foundation for Postgraduate[grant number CX2018B550].
文摘Considering that almost all existing solutions of fusing different reconstructed results require experts’opinions and the issue of how to fuse probabilistic results and mixed results has not been discussed.Two solutions are proposed.The first is based on the Monte Carlo Method(FMCM),while the second is based on the Sub-Interval Technique(FSIT).The method based on FMCM generates sample points according to the distribution of each uncertain result firstly,and then gives out the cumulative distribution function of the final fused result by statistical analysis.The method based on FSIT gets the result fusion interval set according to lower and upper bounds of all interval results and a given length d of each sub-interval firstly,and then calculate the weighted matrix of the result fusion interval.As a result,the cumulative distribution function of the final fused result can also be given out by statistical analysis.Finally,three real accidents are given to demonstrate the methods of FMCM and FSIT,the results of which show that both work well in practice.
文摘Mutations in presenilin 1(PS1)gene are closely associated with the early onset of familial Alzheimer’s disease(EOFAD).The fusion genes,GFP-PS1(recombinant plasmid pEGFP-C1-PS1)and PS1-GFP(recombinant plasmid pEGFP-N2-PS1)were constructed to study the subcellular localization of PS1 holoprotein.Recombinant plasmids were transiently transfected into two cell lines,HEK293 and CHO,respectively,using the green fluorescence from GFP(green fluorescence protein)as the PS1 localization signal.Then,we observed green fluorescence with a SPOT II(Olympus,BH2)and CONFOCAL microscope(Olympus,FV300)under 488 nm.The results show that PS1 located on the nuclear envelope.A few can be found on the cellular membrane and in the cytosol in a non-homogeneous distribution.
基金Southwest Medical University 2023 Education and Teaching Reform Research Project(No.27)。
文摘Diseases of the blood system are highly complicated and involve many aspects.This article aimed to put forward the necessity of integrating quality and professional education,the necessity of learning logic,and the importance of establishing an integrated medical education model when teaching about blood system diseases.According to the requirements of the new medical science,this article puts forward the integration of an“online+offline+clinical”medical education mode based on the social learning theory and a learning evaluation mode based on medical literacy.The fundamental task of cultivating human beings into clinical medical talents with professional ethics,independent learning abilities,interpersonal communication abilities,complex problem-solving abilities,innovative consciousness,and critical thinking was implemented.This article aims to propose an improved construction plan to create a new and improved teaching system in medicine.
文摘The general use of aluminium as an indentation standard for the iteration of contact heights for the determination of ISO-14577 hardness and elastic modulus is challenged because of as yet not appreciated phase-changes in the physical force-depth standard curve that seemed to be secured by claims from 1992. The physical and mathematical analyses with closed formulas avoid the still world-wide standardized energy-law violation by not reserving 33.33% (h2 belief) (or 20% h3/2 physical law) of the loading force and thus energy for all not depth producing events but using 100% for the depth formation is a severe violation of the energy law. The not depth producing part of the indentation work cannot be done with zero energy! Both twinning and structural phase-transition onsets and normalized phase-transition energies are now calculated without iterations but with physically correct closed arithmetic equations. These are reported for Berkovich and cubecorner indentations, including their comparison on geometric grounds and an indentation standard without mechanical twinning is proposed. Characteristic data are reported. This is the first detection of the indentation twinning of aluminium at room temperature and the mechanical twinning of fused quartz is also new. Their disqualification as indentation standards is established. Also, the again found higher load phase-transitions disqualify aluminium and fused quartz as ISO-ASTM 14577 (International Standardization Organization and American Society for Testing and Materials) standards for the contact depth “hc” iterations. The incorrect and still world-wide used black-box values for H- and Er-values (the latter are still falsely called “Young’s moduli” even though they are not directional) and all mechanical properties that depend on them. They lack relation to bulk moduli from compression experiments. Experimentally obtained and so published force vs depth parabolas always follow the linear FN = kh3/2 + Fa equation, where Fa is the axis-cut before and after the phase-transition branches (never “h2” as falsely enforced and used for H, Er and giving incorrectly calculated parameters). The regression slopes k are the precise physical hardness values, which for the first time allow for precise calculation of the mechanical qualities by indentation in relation to the geometry of the indenter tip. Exactly 20% of the applied force and thus energy is not available for the indentation depth. Only these scientific k-values must be used for AI-advises at the expense of falsely iterated indentation hardness H-values. Any incorrect H-ISO-ASTM and also the iterated Er-ISO-ASTM modulus values of technical materials in artificial intelligence will be a disaster for the daily safety. The AI must be told that these are unscientific and must therefore be replaced by physical data. Iterated data (3 and 8 free parameters!) cannot be transformed into physical data. One has to start with real experimental loading curves and an absolute ZerodurR standard that must be calibrated with standard force and standard length to create absolute indentation results. .
基金supported by the National Natural Science Foundation of China(Grant No.51901082)the National Postdoctoral Program for Innovative Talents(BX20200137)the National Defense Basic Scientific Research Program of China(JCKY2018110C060)。
文摘Additive manufacturing(AM)is a free-form technology that shows great potential in the integrated creation of three-dimensional(3D)electronics.However,the fabrication of 3D conformal circuits that fulfill the requirements of high service temperature,high conductivity and high resolution remains a challenge.In this paper,a hybrid AM method combining the fused deposition modeling(FDM)and hydrophobic treatment assisted laser activation metallization(LAM)was proposed for manufacturing the polyetheretherketone(PEEK)-based 3D electronics,by which the conformal copper patterns were deposited on the 3D-printed PEEK parts,and the adhesion between them reached the 5B high level.Moreover,the 3D components could support the thermal cycling test from-55℃ to 125℃ for more than 100 cycles.Particularly,the application of a hydrophobic coating on the FDM-printed PEEK before LAM can promote an ideal catalytic selectivity on its surface,not affected by the inevitable printing borders and pores in the FDM-printed parts,then making the resolution of the electroless plated copper lines improved significantly.In consequence,Cu lines with width and spacing of only60μm and 100μm were obtained on both as-printed and after-polished PEEK substrates.Finally,the potential of this technique to fabricate 3D conformal electronics was demonstrated.
基金The authors gratefully acknowledge the support provided by the National Natural Science Foundation of China(Nos.52250006 and 52075482)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study(No.SNZJU-SIAS-004).
文摘Ideal tissue engineering scaffolds need interconnected pores and high porosity to enable cell survival,migration,proliferation,and differentiation.However,obtaining a high-resolution structure is difficult with traditional one-temperature control fused deposition modeling(FDM).In this study,we propose a dual-temperature control method to improve printability.A numerical model is developed in which the viscosity is a function of temperature and shear rate to study the influence of two different temperature control modes.Quantitative tests are used to assess filament formation and shape fidelity,including one-dimensional filament printing,deposition at corners,fusion,and collapse.By using dual-temperature control,the width of the deposited poly(ε-caprolactone)filament is reduced to 50μm.The comparative results of both the experimental method and numerical simulation suggest that the dual-temperature control FDM can manufacture spatially arranged constructs and presents a promising application in tissue engineering。
文摘The urgent need to develop customized functional products only possible by 3D printing had realized when faced with the unavailability of medical devices like surgical instruments during the coronavirus-19 disease and the ondemand necessity to perform surgery during space missions.Biopolymers have recently been the most appropriate option for fabricating surgical instruments via 3D printing in terms of cheaper and faster processing.Among all 3D printing techniques,fused deposition modelling(FDM)is a low-cost and more rapid printing technique.This article proposes the fabrication of surgical instruments,namely,forceps and hemostat using the fused deposition modeling(FDM)process.Excellent mechanical properties are the only indicator to judge the quality of the functional parts.The mechanical properties of FDM-processed parts depend on various process parameters.These parameters are layer height,infill pattern,top/bottom pattern,number of top/bottom layers,infill density,flow,number of shells,printing temperature,build plate temperature,printing speed,and fan speed.Tensile strength and modulus of elasticity are chosen as evaluation indexes to ascertain the mechanical properties of polylactic acid(PLA)parts printed by FDM.The experiments have performed through Taguchi’s L27orthogonal array(OA).Variance analysis(ANOVA)ascertains the significance of the process parameters and their percent contributions to the evaluation indexes.Finally,as a multiobjective optimization technique,grey relational analysis(GRA)obtains an optimal set of FDM process parameters to fabricate the best parts with comprehensive mechanical properties.Scanning electron microscopy(SEM)examines the types of defects and strong bonding between rasters.The proposed research ensures the successful fabrication of functional surgical tools with substantial ultimate tensile strength(42.6 MPa)and modulus of elasticity(3274 MPa).