The increasingly stringent performance requirement in integrated circuit manufacturing, characterized by smaller feature sizes and higher productivity, necessitates the wafer stage executing a extreme motion with the ...
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The increasingly stringent performance requirement in integrated circuit manufacturing, characterized by smaller feature sizes and higher productivity, necessitates the wafer stage executing a extreme motion with the accuracy in terms of nanometers. This demanding requirement witnesses a widespread application of iterative learning control(ILC), given the repetitive nature of wafer scanning. ILC enables substantial performance improvement by using past measurement data in combination with the system model knowledge. However, challenges arise in cases where the data is contaminated by the stochastic noise, or when the system model exhibits significant uncertainties, constraining the achievable performance. In response to this issue, an extended state observer(ESO) based adaptive ILC approach is proposed in the frequency *** being model-based, it utilizes only a rough system model and then compensates for the resulting model uncertainties using an ESO, thereby achieving high robustness against uncertainties with minimal modeling effort. Additionally, an adaptive learning law is developed to mitigate the limited performance in the presence of stochastic noise, yielding high convergence accuracy yet without compromising convergence speed. Simulation and experimental comparisons with existing model-based and data-driven inversion-based ILC validate the effectiveness as well as the superiority of the proposed method.
The metamaterial based on external meshing gears(MEG) is designed based on the principle of external meshing gear transmission. Based on the meshing transmission principle of external meshing gears and planetary gear ...
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The metamaterial based on external meshing gears(MEG) is designed based on the principle of external meshing gear transmission. Based on the meshing transmission principle of external meshing gears and planetary gear trains, the internal and external gear rings are designed. Based on the internal and external gear rings, the metamaterial based on inner and outer planetary gear trains(MIP) is designed to study the shear modulus, Young's modulus, and amplitude-frequency characteristics of the metamaterial based on gears at different angles. The effects of the number of planetary gears on the physical characteristics of the MIP are studied. The results show that the MEG can be continuously adjusted by adjusting the shear modulus and Young's modulus due to its meshing characteristics. With the same number of gears, the adjustment range of the MIP is larger than the adjustment range of the MEG. When the number of planetary gears increases, the adjustment range of the MIP decreases. Moreover, when the metamaterial based on gears rotates, the harmonic response changes with the change of the angle.
To elucidate the mechanisms of regulating the microstructure uniformity in 7050 aluminum forgings through surface cumulative plastic deformation(SCPD),the microstructure under different solution treatments was investi...
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To elucidate the mechanisms of regulating the microstructure uniformity in 7050 aluminum forgings through surface cumulative plastic deformation(SCPD),the microstructure under different solution treatments was investigated using metallographic observation(OM),electron backscatter diffraction(EBSD),transmission electron microscopy(TEM),and X-ray diffraction(XRD).The findings demonstrate that the most uniform microstructure in the forgings is achieved with a solution treatment at 470℃for 30 *** SCPD process generates a significant number of needle-shaped precipitates,resulting in a higher dislocation density and stored *** treatments alleviate the pinning effect of second-phase particles and facilitate static recrystallization(SRX)in forgings,leading to a reduction in grain ***,mechanical testing results demonstrate 7%−13%increase in tensile strength and more uniform elongation of the forgings in different directions.
Quantum algorithms offer more enhanced computational efficiency in comparison to their classical counterparts when solving specific tasks. In this study, we implement the quantum permutation algorithm utilizing a pola...
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Quantum algorithms offer more enhanced computational efficiency in comparison to their classical counterparts when solving specific tasks. In this study, we implement the quantum permutation algorithm utilizing a polar molecule within an external electric field. The selection of the molecular qutrit involves the utilization of field-dressed states generated through the pendular modes of SrO. Through the application of multi-target optimal control theory, we strategically design microwave pulses to execute logical operations, including Fourier transform,oracle Ufoperation, and inverse Fourier transform within a three-level molecular qutrit *** observed high fidelity of our outcomes is intricately linked to the concept of the quantum speed limit, which quantifies the maximum speed of quantum state manipulation. Subsequently,we design the optimized pulse sequence to successfully simulate the quantum permutation algorithm on a single SrO molecule, achieving remarkable fidelity. Consequently, a quantum circuit comprising a single qutrit suffices to determine permutation parity with just a single function evaluation. Therefore, our results indicate that the optimal control theory can be well applied to the quantum computation of polar molecular systems.
As a highly promising conductive polymer material,the synthesis method,structure regulation,and performance improvement of polyaniline(PANI)are hot research *** this work,the radiation-induced polymerization of anilin...
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As a highly promising conductive polymer material,the synthesis method,structure regulation,and performance improvement of polyaniline(PANI)are hot research *** this work,the radiation-induced polymerization of aniline in HNO_(3)solution was successfully achieved at room temperature without the use of chemical *** the analysis of the radiation chemical reactions of inorganic acids and nitrate salt solutions,the characterization of the intermediate free radicals in the irradiated systems,and the influence of the pH of the solutions on the polymerization activity and product morphologies,the radiation-induced polymerization mechanism of aniline is discussed in detail and *** at a condition of[HNO_(3)]>[aniline],i.e.,pHstate,which can be used for the preparation of PANI supercapacitors with better electrochemical properties than those prepared by chemical oxidation under the same *** work presents a new radiation-synthesis method and polymerization mechanism of PANI,which not only expands the application of radiation technique in the field of polymer synthesis,but also provides a new idea for the structural regulation and electrochemical property optimization of PANI.
Previous studies have revealed that typhoons can affect the ionosphere. This paper uses GNSS observations provided by GNSS tracking stations of Taiwan region, ERA5 gravity wave dissipation products,and Himawari-8 band...
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Previous studies have revealed that typhoons can affect the ionosphere. This paper uses GNSS observations provided by GNSS tracking stations of Taiwan region, ERA5 gravity wave dissipation products,and Himawari-8 band 07 brightness temperature observation data to analyze the impact of Typhoon Meranti on Taiwan region's ionosphere from September 13 to 15, 2016. In addition to the daily effects of traveling ionospheric disturbances(TIDs), TIDs of various intensities caused by Meranti-induced gravity waves were observed during this period, which is inseparable from the state of the typhoon and the topographic features during its progress. The ionospheric disturbance caused by the edge of a typhoon is usually larger than that at the typhoon eye. When the typhoon approached Taiwan region with high intensity on September 14, it was observed that the gravity waves caused by the typhoon had a wavelength of about 174-293 km, a period of 13.5-23.5 min, and a propagation speed of 142-302 m/s. When the vortex structure of a typhoon interacts with complex surfaces such as mountains, it is easier to excite more medium-scale gravity waves. The origin that excites gravity waves and causes ionospheric anomalies is different from the location of the typhoon eye and changes over time. The gravity waves caused by the typhoon lasted for three days in the central mountains of Taiwan region. Still, background wind conditions restricted the propagation of gravity waves from the mesosphere to the thermosphere and led to TID predominantly concentrated between 06:00 and 13:00 UT each day.
Conventional metasurfaces for terahertz polarization are limited to performing lateral(in the x-y plane)polarization control of the output *** such cases,the polarization state remains unchanged in each output plane a...
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Conventional metasurfaces for terahertz polarization are limited to performing lateral(in the x-y plane)polarization control of the output *** such cases,the polarization state remains unchanged in each output plane along the propagation ***,we propose a terahertz polarization metasurface that operates longitudinally(i.e.,along the z-axis direction of propagation),which modifies the polarization state of each output plane throughout the propagation *** designed metasurface can control the phase delays of the left-handed and right-handed circularly polarized(LCP and RCP)components of the incident terahertz *** enables the LCP beam and RCP beam to converge to the z-axis through distinct paths,creating a Bessel *** proposed design achieved a linearly polarized terahertz wave including both LCP and RCP components with a precise phase differenceΔφat each point within a certain range along the ***Δφvaries as the propagation distance,resulting in a rotated linearly polarized output wave along the propagation path,while the rotation angle ranges from 0 toπ.Based on the variable property of longitudinal polarization,we propose an application concept of dielectric refractive index sensing,in which an additional medium is placed in the terahertz propagation path and the unknown refractive index is determined by detecting the rotation angle of the output polarization ***,the device might find potential applications in variable media excitation,terahertz communication,and terahertz radar ranging.
To develop high-hardness and high-strength lightweight high entropy alloys (LHEAs),a series of CoxAlNbTiVCr alloys were *** phase constitution,distribution,and crystal structure of the Laves phase in alloys can be a...
To develop high-hardness and high-strength lightweight high entropy alloys (LHEAs),a series of CoxAlNbTiVCr alloys were *** phase constitution,distribution,and crystal structure of the Laves phase in alloys can be altered by adjusting the composition of HEAs,which in turn influences their mechanical *** Nb Ti VCr (x=0,0.5,1,1.5,and 2,atomic ratio percentage) LHEAs were designed and prepared to characterize the microstructure and tailor the mechanical *** introduction of Co changes the microstructure of LHEAs from a single B2 structure to a mixture dendrite structure,which consists of B2 phase,C14 and C15 Laves *** the C14 and C15 Laves phases exhibit coupled *** parameters including mixing enthalpy (ΔHmix),valence electron concentration (VEC),atomic radius size (δ),mixing entropy (ΔS),and electronegativity difference (Δχ) are used to predict the formation of B2 and Laves phase in *** the Co content increases from 0 to 1.5at.%,Laves phase volume fraction gradually increases,which leads to an enhancement in the compressive strength from 1,520.8 MPa to 1,844.4 ***1.5Al Nb Ti VCr alloy exhibits the maximum Vickers hardness of 699.4 *** improvement of mechanical properties mainly originates from solid solution strengthening and second phase strengthening.
Sequence-activated chemiluminescence(CL)technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial *** fundamental principle behind sequence-activated CL...
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Sequence-activated chemiluminescence(CL)technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial *** fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest,thus enabling high-contrast signals under complex physiological *** sequential activation could be triggered by enzymes,reactive oxygen species(ROS),biothiols or changes in the *** unique sequence-activated CL probes bestow several advantages,including minimal background,deep-tissue penetration,and the ability of non-invasive or minimally invasive *** sequence-activated CL techniques represent a significant advancement in molecular imaging and *** this mini-review,we focus on the latest developments in sequential CL probes,addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.
Although the plastic loading can enhance creep deformation and yield strength,the anisotropic Stress Relaxation Aging(SRA)behavior and mechanism under plastic loading remain unclear,which presents a significant challe...
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Although the plastic loading can enhance creep deformation and yield strength,the anisotropic Stress Relaxation Aging(SRA)behavior and mechanism under plastic loading remain unclear,which presents a significant challenge in accurately shaping aluminum alloy *** this study,the SRA behavior of 2195-T4 Al-Cu-Li alloys were thoroughly studied under initial loading stresses within the elastic(210/250 MPa)and plastic(380/420 MPa)ranges at 180℃by stress relaxation and tensile tests as well as microstructure *** findings reveal that compared with those under elastic loadings,in-plane anisotropy(IPA)values of the stress relaxation amount,yield strength and fracture elongation under plastic loadings are reduced by 60%–80%,70%–90% and 72%–89%,***,IPA values of precipitate size in grains and PrecipitationFree Zones(PFZ)width at grain boundaries under plastic loading decrease by 31.4%and 94.4%*** results indicate plastic loading significantly weakens the anisotropic SRA behavior,owing to numerous uniformly distributed fine T1phases and small IPA values of both T1precipitates size and PFZ width in various loading *** with those of elastic loadingaged alloys,yield strength of plastic loading-aged alloys shows high strength-ductility because of the combined effect of closely dispersed fine T1precipitates,narrowed PFZ and numerous sheared and rotated T1phases at different locations during tensile *** uniformly distributed larger Kernel Average Misorientation(KAM)and Schmidt factor values of the plastic loading-aged alloy,as well as the cross-slip generated,also help to enhance the strength and ductility of the alloy.
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