Material Removal Mechanism and Force Modeling in Ultrasonic Vibration-Assisted Micro-Grinding Biological Bone

Micro-grinding with a spherical grinding head has been deemed an indispensable method in high-risk surgeries, such as neurosurgery and spine surgery, where bone grinding has long been plagued by the technical bottleneck of mechanical stress-induced crack damage. In response to this challenge, the ultrasound-assisted biological bone micro-grinding novel process with a spherical grinding head has been proposed by researchers. Force modeling is a prerequisite for process parameter determination in orthopedic surgery, and the difculty in establishing and accurately predicting bone micro-grinding force prediction models is due to the geometric distribution of abrasive grains and the dynamic changes in geometry and kinematics during the cutting process. In addressing these critical needs and technical problems, the shape and protrusion heights of the wear particle of the spherical grinding head were frst studied, and the gradual rule of the contact arc length under the action of high-speed rotating ultrasonic vibration was proposed. Second, the mathematical model of the maximum thickness of undeformed chips under ultrasonic vibration of the spherical grinding head was established. Results showed that ultrasonic vibration can reduce the maximum thickness of undeformed chips and increase the range of ductile and bone meal removals, revealing the mechanism of reducing grinding force. Further, the dynamic grinding behavior of diferent layers of abrasive particles under diferent instantaneous interaction states was studied. Finally, a prediction model of micro-grinding force was established in accordance with the relationship between grinding force and cutting depth, revealing the mechanism of micro-grinding force transfer under ultrasonic vibration. The theoretical model’s average deviations are 10.37% in x-axis direction, 6.85% in y-axis direction, and 7.81% in z-axis direction compared with the experimental results. This study provides theoretical guidance and technical support for clinical bone micro-grinding.

Ultrafast magneto-optical dynamics in nickel(111)single crystal studied by the integration of ultrafast reflectivity and polarimetry probes

With the integration of ultrafast reflectivity and polarimetry probes,we observed carrier relaxation and spin dynamics induced by ultrafast laser excitation of Ni(111)single crystals.The carrier relaxation time within the linear excitation range reveals that electron-phonon coupling and dissipation of photon energy into the bulk of the crystal take tens of picoseconds.On the other hand,the observed spin dynamics indicate a longer time of about 120 ps.To further understand how the lattice degree of freedom is coupled with these dynamics may require the integration of an ultrafast diffraction probe.

Electrostatic atomization minimum quantity lubrication machining:from mechanism to application

Metal cutting fluids(MCFs)under flood conditions do not meet the urgent needs of reducing carbon emission.Biolubricant-based minimum quantity lubrication(MQL)is an effective alternative to flood lubrication.However,pneumatic atomization MQL has poor atomization properties,which is detrimental to occupational health.Therefore,electrostatic atomization MQL requires preliminary exploratory studies.However,systematic reviews are lacking in terms of capturing the current research status and development direction of this technology.This study aims to provide a comprehensive review and critical assessment of the existing understanding of electrostatic atomization MQL.This research can be used by scientists to gain insights into the action mechanism,theoretical basis,machining performance,and development direction of this technology.First,the critical equipment,eco-friendly atomization media(biolubricants),and empowering mechanisms of electrostatic atomization MQL are presented.Second,the advanced lubrication and heat transfer mechanisms of biolubricants are revealed by quantitatively comparing MQL with MCF-based wet machining.Third,the distinctive wetting and infiltration mechanisms of electrostatic atomization MQL,combined with its unique empowering mechanism and atomization method,are compared with those of pneumatic atomization MQL.Previous experiments have shown that electrostatic atomization MQL can reduce tool wear by 42.4%in metal cutting and improve the machined surface Ra by 47%compared with pneumatic atomization MQL.Finally,future development directions,including the improvement of the coordination parameters and equipment integration aspects,are proposed.

ecent Advances in the Science of Burst Wave Lithotripsy and Ultrasonic Propulsion

Objective.Retinal degeneration involving progressive deterioration and loss of function of photoreceptors is a major cause of permanent vision loss worldwide.Strategies to treat these incurable conditions incorporate retinal prostheses via electrically stimulating surviving retinal neurons with implanted devices in the eye,optogenetic therapy,and sonogenetic therapy.Existing challenges of these strategies include invasive manner,complex implantation surgeries,and risky gene therapy.Methods and Results.Here,we show that direct ultrasound stimulation on the retina can evoke neuron activities from the visual centers including the superior colliculus and the primary visual cortex(V1),in either normal-sighted or retinal degenerated blind rats in vivo.The neuron activities induced by the customized spherically focused 3.1 MHz ultrasound transducer have shown both good spatial resolution of 250μm and temporal resolution of 5 Hz in the rat visual centers.An additional customized 4.4 MHz helical transducer was further implemented to generate a static stimulation pattern of letter forms.Conclusion.Our findings demonstrate that ultrasound stimulation of the retina in vivo is a safe and effective approach with high spatiotemporal resolution,indicating a promising future of ultrasound stimulation as a novel and noninvasive visual prosthesis for translational applications in blind patients.

Development of Moderate Intensity Focused Ultrasound(MIFU)for Ocular Drug Delivery

The purpose of this study is to develop a method for delivering antiinflammatory agents of high molecular weight(e.g.,Avastin)into the posterior segment that does not require injections into the eye(i.e.,intravitreal injections;IVT).Diseases affecting the posterior segment of the eye are currently treated with monthly to bimonthly intravitreal injections,which can predispose patients to severe albeit rare complications like endophthalmitis,retinal detachment,traumatic cataract,and/or increased intraocular.In this study,we show that one time moderate intensity focused ultrasound(MIFU)treatment can facilitate the penetration of large molecules across the scleral barrier,showing promising evidence that this is a viable method to deliver high molecular weight medications not invasively.To validate the efficacy of the drug delivery system,IVT injections of vascular endothelial growth factor(VEGF)were used to create an animal model of retinopathy.The creation of this model allowed us to test anti-VEGF medications and evaluate the efficacy of the treatment.In vivo testing showed that animals treated with our MIFU device improved on the retinal tortuosity and clinical dilation compared to the control group while evaluating fluorescein angiogram(FA)Images.

Temperature field model in surface grinding: a comparative assessment

Grinding is a crucial process in machining workpieces because it plays a vital role in achieving the desired precision and surface quality.However,a significant technical challenge in grinding is the potential increase in temperature due to high specific energy,which can lead to surface thermal damage.Therefore,ensuring control over the surface integrity of workpieces during grinding becomes a critical concern.This necessitates the development of temperature field models that consider various parameters,such as workpiece materials,grinding wheels,grinding parameters,cooling methods,and media,to guide industrial production.This study thoroughly analyzes and summarizes grinding temperature field models.First,the theory of the grinding temperature field is investigated,classifying it into traditional models based on a continuous belt heat source and those based on a discrete heat source,depending on whether the heat source is uniform and continuous.Through this examination,a more accurate grinding temperature model that closely aligns with practical grinding conditions is derived.Subsequently,various grinding thermal models are summarized,including models for the heat source distribution,energy distribution proportional coefficient,and convective heat transfer coefficient.Through comprehensive research,the most widely recognized,utilized,and accurate model for each category is identified.The application of these grinding thermal models is reviewed,shedding light on the governing laws that dictate the influence of the heat source distribution,heat distribution,and convective heat transfer in the grinding arc zone on the grinding temperature field.Finally,considering the current issues in the field of grinding temperature,potential future research directions are proposed.The aim of this study is to provide theoretical guidance and technical support for predicting workpiece temperature and improving surface integrity.

电场参数对雾化特性及微量润滑磨削性能影响的实验研究

为了探究针-板电极电场参数对雾化特性微量润滑磨削性能的影响,通过调节电压幅值和电极间距进行微量润滑平面磨削实验,根据所得雾化锥角、雾滴粒径算术平均值、磨削力及表面粗糙度Ra值进行机理分析。实验结果表明静电雾化微量润滑在高压静电场的参与下,液滴荷电后会发生二次甚至多次雾化。随着电压幅值的升高,雾化锥角增大,雾滴的平均粒径减小并扩散均匀,同时润滑液的润滑性能也有所提高。在电压幅值一定,电极间距为160 mm时,获得最优的润滑性能;在电极间距一定,电压幅值为50 k V时,相比于无静电微量润滑,比切向磨削力Ft'、比法向磨削力Fn'及表面粗糙度R_a值,分别减小25.01%、15.08%、22.18%,获得最优的润滑性能。

RF magnetron sputtering induced the perpendicular magnetic anisotropy modification in Pt/Co based multilayers

We demonstrate that radio frequency(RF)magnetron sputtering technique can modify the perpendicular magnetic anisotropy(PMA)of Pt/Co/normal metal(NM)thin films.Influence of ion irradiation during RF magnetron sputtering should not be neglected and it can weaken PMA of the deposited magnetic films.The magnitude of this influence can be controlled by tuning RF magnetron sputtering deposition conditions and the upper NM layer thickness.According to the stopping and range of ions in matter(SRIM)simulation results,defects such as displacement atoms and vacancies in the deposited film will increase after the RF magnetron sputtering,which can account for the weakness of PMA.The amplitude changes of the Hall resistance and the threshold current intensity of spin orbit torque(SOT)induced magnetization switching also can be modified.Our study could be useful for controlling magnetic properties of PMA films and designing new type of SOT-based spintronic devices.

Machinability of ultrasonic vibration-assisted micro-grinding in biological bone using nanolubricant

Bone grinding is an essential and vital procedure in most surgical operations.Currently,the insufficient cooling capacity of dry grinding,poor visibility of drip irrigation surgery area,and large grinding force leading to high grinding temperature are the technical bottlenecks of micro-grinding.A new micro-grinding process called ultrasonic vibration-assisted nanoparticle jet mist cooling(U-NJMC)is innovatively proposed to solve the technical problem.It combines the advantages of ultrasonic vibration(UV)and nanoparticle jet mist cooling(NJMC).Notwithstanding,the combined effect of multi parameter collaborative of U-NJMC on cooling has not been investigated.The grinding force,friction coefficient,specific grinding energy,and grinding temperature under dry,drip irrigation,UV,minimum quantity lubrication(MQL),NJMC,and U-NJMC micro-grinding were compared and analyzed.Results showed that the minimum normal grinding force and tangential grinding force of U-NJMC micro-grinding were 1.39 and 0.32 N,which were 75.1%and 82.9%less than those in dry grinding,respectively.The minimum friction coefficient and specific grinding energy were achieved using U-NJMC.Compared with dry,drip,UV,MQL,and NJMC grinding,the friction coefficient of U-NJMC was decreased by 31.3%,17.0%,19.0%,9.8%,and 12.5%,respectively,and the specific grinding energy was decreased by 83.0%,72.7%,77.8%,52.3%,and 64.7%,respectively.Compared with UV or NJMC alone,the grinding temperature of U-NJMC was decreased by 33.5%and 10.0%,respectively.These results showed that U-NJMC provides a novel approach for clinical surgical micro-grinding of biological bone.

Coverless Video Steganography Based on Frame Sequence Perceptual Distance Mapping

Most existing coverless video steganography algorithms use a particular video frame for information hiding.These methods do not reflect the unique sequential features of video carriers that are different from image and have poor robustness.We propose a coverless video steganography method based on frame sequence perceptual distance mapping.In this method,we introduce Learned Perceptual Image Patch Similarity(LPIPS)to quantify the similarity between consecutive video frames to obtain the sequential features of the video.Then we establish the relationship map between features and the hash sequence for information hiding.In addition,the MongoDB database is used to store the mapping relationship and speed up the index matching speed in the information hiding process.Experimental results show that the proposed method exhibits outstanding robustness under various noise attacks.Compared with the existing methods,the robustness to Gaussian noise and speckle noise is improved by more than 40%,and the algorithm has better practicability and feasibility.

Herbal formula BaWeiBaiDuSan alleviates polymicrobial sepsis-induced liver injury via increasing the gut microbiota Lactobacillus johnsonii and regulating macrophage anti-inflammatory activity in mice

Sepsis-induced liver injury(SILI)is an important cause of septicemia deaths.BaWeiBaiDuSan(BWBDS)was extracted from a formula of Panax ginseng C.A.Meyer,Lilium brownie F.E.Brown ex Miellez var.viridulum Baker,Polygonatum sibiricum Delar.ex Redoute,Lonicera japonica Thunb.,Hippophae rhamnoides Linn.,Amygdalus Communis Vas,Platycodon grandiflorus(Jacq.)A.DC.,and Cortex Phelloderdri.Herein,we investigated whether the BWBDS treatment could reverse SILI by the mechanism of modulating gut microbiota.BWBDS protected mice against SILI,which was associated with promoting macrophage anti-inflammatory activity and enhancing intestinal integrity.BWBDS selectively promoted the growth of Lactobacillus johnsonii(L.johnsonii)in cecal ligation and puncture treated mice.Fecal microbiota transplantation treatment indicated that gut bacteria correlated with sepsis and was required for BWBDS anti-sepsis effects.Notably,L.johnsonii significantly reduced SILI by promoting macrophage anti-inflammatory activity,increasing interleukin-10+M2 macrophage production and enhancing intestinal integrity.Furthermore,heat inactivation L.johnsonii(HI-L.johnsonii)treatment promoted macrophage anti-inflammatory activity and alleviated SILI.Our findings revealed BWBDS and gut microbiota L.johnsonii as novel prebiotic and probiotic that may be used to treat SILI.The potential underlying mechanism was at least in part,via L.johnsonii-dependent immune regulation and interleukin-10+M2 macrophage production.

Mechanical behavior and semiempirical force model of aerospace aluminum alloy milling using nano biological lubricant

Aerospace aluminum alloy is the most used structural material for rockets,aircraft,spacecraft,and space stations.The deterioration of surface integrity of dry machining and the insufficient heat transfer capacity of minimal quantity lubrication have become the bottleneck of lubrication and heat dissipation of aerospace aluminum alloy.However,the excellent thermal conductivity and tribological properties of nanofluids are expected to fill this gap.The traditional milling force models are mainly based on empirical models and finite element simulations,which are insufficient to guide industrial manufacturing.In this study,the milling force of the integral end milling cutter is deduced by force analysis of the milling cutter element and numerical simulation.The instantaneous milling force model of the integral end milling cutter is established under the condition of dry and nanofluid minimal quantity lubrication(NMQL)based on the dual mechanism of the shear effect on the rake face of the milling cutter and the plow cutting effect on the flank surface.A single factor experiment is designed to introduce NMQL and the milling feed factor into the instantaneous milling force coefficient.The average absolute errors in the prediction of milling forces for the NMQL are 13.3%,2.3%,and 7.6%in the x-,y-,and z-direction,respectively.Compared with the milling forces obtained by dry milling,those by NMQL decrease by 21.4%,17.7%,and 18.5%in the x-,y-,and z-direction,respectively.

Whether Probiotic Supplementation Benefits Rheumatoid Arthritis Patients： A Systematic Review and Meta-Analysis

Gut and oral microflora are important factors in the pathogenesis and development of rheumatoid arthritis(RA). Recent studies have shown that probiotic supplements have beneficial consequences on experimental arthritis in rats. However, results from randomized clinical trials on the effects of probiotics have not been consistent. The aim of this study was to systematically review the existing evidence for the effects of probiotic intervention in RA. We included randomized controlled trials(RCTs) of RA patients receiving stable treatment with disease-modifying anti-rheumatic drugs(DMARDs) that:(1) were combined with additional probiotic supplements or(2) were combined with either no additional supplements or only a placebo treatment. Statistical analysis was performed using Review Manager 5.3.3.Six randomized clinical trials were eligible for inclusion in the meta-analysis, with 249 participants in total. The results showed that the probiotic intervention treatment has not yet achieved significant improvement in the American College of Rheumatology 20% improvement criteria(ACR20) score and the disease activity score in 28 joints(DAS28). The laboratory index C-reactive protein(CRP)(mg·L–1) was significantly reduced in the intervention group. The expression of inflammatory cytokines tumor necrosis factor(TNF)-α and interleukine(IL)-1β was also significantly reduced, while IL-10 expression increased in the probiotic intervention groups. This article is the first systematic review and meta-analysis providing a comprehensive assessment of the benefits of treating RA with probiotics. We found that probiotic supplementation may show a limited improvement in RA therapy in existing reports because of a lack of sufficiently high-quality work on the part of clinicians. More multi-centered, large-sample RCTs are needed in order to evaluate the benefits of probiotics in RA treatment.

Nanoparticle-enhanced coolants in machining:mechanism,application,and prospects

Nanoparticle-enhanced coolants(NPECs)are increasingly used in minimum quantity lubrication(MQL)machining as a green lubricant to replace conventional cutting fluids to meet the urgent need for carbon emissions and achieve sustainable manufacturing.However,the thermophysical properties of NPEC during processing remain unclear,making it difficult to provide precise guidance and selection principles for industrial applications.Therefore,this paper reviews the action mechanism,processing properties,and future development directions of NPEC.First,the laws of influence of nano-enhanced phases and base fluids on the processing performance are revealed,and the dispersion stabilization mechanism of NPEC in the preparation process is elaborated.Then,the unique molecular structure and physical properties of NPECs are combined to elucidate their unique mechanisms of heat transfer,penetration,and antifriction effects.Furthermore,the effect of NPECs is investigated on the basis of their excellent lubricating and cooling properties by comprehensively and quantitatively evaluating the material removal characteristics during machining in turning,milling,and grinding applications.Results showed that turning of Ti‒6Al‒4V with multi-walled carbon nanotube NPECs with a volume fraction of 0.2%resulted in a 34%reduction in tool wear,an average decrease in cutting force of 28%,and a 7%decrease in surface roughness Ra,compared with the conventional flood process.Finally,research gaps and future directions for further applications of NPECs in the industry are presented.

Dynamic human retinal pigment epithelium(RPE)and choroid architecture based on single-cell transcriptomic landscape analysis

The retinal pigment epithelium(RPE)and choroid are located behind the human retina and have multiple functions in the human visual system.Knowledge of the RPE and choroid cells and their gene expression profiles are fundamental for understanding retinal disease mechanisms and therapeutic strategies.Here,we sequenced the RNA of about 0.3 million single cells from human RPE and choroids across two regions and seven ages,revealing regional and age differences within the human RPE and choroid.Cell–cell interactions highlight the broad connectivity networks between the RPE and different choroid cell types.Moreover,the transcription factors and their target genes change during aging.The coding of somatic variations increases during aging in the human RPE and choroid at the single-cell level.Moreover,we identified ELN as a candidate for improving RPE degeneration and choroidal structure during aging.The mapping of the molecular architecture of the human RPE and choroid improves our understanding of the human vision support system and offers potential insights into the intervention targets for retinal diseases.

钌基单原子和团簇催化剂在电催化反应中的竞争和协同效应

单原子和团簇催化剂在电催化领域,尤其是可持续能源存储和转化领域的重要性,得到越来越多地认可.单原子催化剂具有低金属负载和高原子利用效率的优点,但由于其表面自由能常常使得单个原子不稳定而发生聚集.团簇催化剂则因为其高原子利用率以及多样的活性位点,能够克服单原子催化剂在中间体吸附和活化等方面的局限性.钌基催化剂在电催化中有着十分重要的应用前景.然而,准确设计钌基单原子和团簇催化剂的几何和电子结构,并揭示它们之间的结构-性质关系,仍然面临着巨大的挑战.因此,我们对钌基催化剂进行了分类和比较(同源/异源),重点总结了钌基单原子和团簇在电催化领域的竞争和协同效应.近年来,钌基催化剂在析氢反应(HER)方面取得了显著进展,因此着重介绍钌基催化剂在HER中的应用,并涵盖了其他电催化反应、双功能反应(HER/OER、HER/HOR)和电化学有机反应.此外,本文还探讨了钌基单原子和团簇在HER过程中的催化机理.最后,我们指出了在复杂钌基催化剂的工业应用开发策略中所面临的挑战和前景.

Milling surface roughness for 7050 aluminum alloy cavity influenced by nozzle position of nanofluid minimum quantity lubrication

In nanofluid minimum quantity lubrication(NMQL)milling of aviation aluminum alloy,it is the bottleneck problem to adjust the position parameters(target distance,incidence angle,and elevation angle)of the nozzle to improve the surface roughness of milling,which has large and uncontrollable errors.In this paper,the influence law of milling cutter speed,helical angle,and cavity shape on the flow field around the milling cutter was studied,and the optimal nozzle profile parameters were obtained.Using 7050 aluminum alloy as the workpiece material,the milling experiment of the NMQL cavity was conducted by utilizing cottonseed oil-based Al2 O3 nanofluid.Results show that the high velocity of the surrounding air flow field and the strong gas barrier could be attributed to high rotating velocities of the milling cutter.The incidence angle of the nozzle was consistent with the helical angle of the milling cutter,the target distance was appropriate at 25–30 mm,and the elevation angle was suitable at 60°–65°.The range and variance analyses of the signal-to-noise ratio of milling force and roughness were performed,and the chip morphology was observed and analyzed.The results show that the optimal combination of nozzle position parameters was the target distance of 30 mm,the incidence angle of 35°,and the elevation angle of 60°.Among these parameters,target distance had the largest impact on cutting performance with a contribution rate of more than 55%,followed by incidence angle and elevation contribution rate.Analysis by orthogonal experiment revealed that the nozzle position parameters were appropriate,and Ra(0.087 lm)was reduced by 30.4%from the maximum value(0.125 lm).Moreover,Rsm(0.05 mm)was minimum,which was 36%lower than that of the seventh group(Rsm=0.078 mm).

Dual-wavelength in-line digital holography with untrained deep neural networks

Dual-wavelength in-line digital holography(DIDH)is one of the popular methods for quantitative phase imaging of objects with non-contact and high-accuracy features.Two technical challenges in the reconstruction of these objects include suppressing the amplified noise and the twin-image that respectively originate from the phase difference and the phase-conjugated wavefronts.In contrast to the conventional methods,the deep learning network has become a powerful tool for estimating phase information in DIDH with the assistance of noise suppressing or twin-image removing ability.However,most of the current deep learning-based methods rely on supervised learning and training instances,thereby resulting in weakness when it comes to applying this training to practical imaging settings.In this paper,a new DIDH network(DIDH-Net)is proposed,which encapsulates the prior image information and the physical imaging process in an untrained deep neural network.The DIDHNet can effectively suppress the amplified noise and the twin-image of the DIDH simultaneously by automatically adjusting the weights of the network.The obtained results demonstrate that the proposed method with robust phase reconstruction is well suited to improve the imaging performance of DIDH.

Synergistic osteogenic and angiogenic effects of KP and QK peptides incorporated with an injectable and self-healing hydrogel for efficient bone regeneration

Irregular defects generated by trauma or surgery in orthopaedics practice were usually difficult to be fitted by the preformed traditional bone graft substitute. Therefore, the injectable hydrogels have attracted an increasing interest for bone repair because of their fittability and mini-invasivity. However, the uncontrollable spreading or mechanical failures during its manipulation remain a problem to be solved. Moreover, in order to achieve vascularized bone regeneration, alternatives of osteogenic and angiogenic growth factors should be adopted to avoid the problem of immunogenicity and high cost. In this study, a novel injectable self-healing hydrogel system (GMO hydrogel) loaded with KP and QK peptides had been developed for enhancing vascularized regeneration of small irregular bone defect. The dynamic imine bonds between gelatin methacryloyl and oxidized dextran provided the GMO hydrogel with self-healing and shear-thinning abilities, which led to an excellent injectability and fittability. By photopolymerization of the enclosed GelMA, GMO hydrogel was further strengthened and thus more suitable for bone regeneration. Besides, the osteogenic peptide KP and angiogenic peptide QK were tethered to GMO hydrogel by Schiff base reaction, leading to desired releasing profiles. In vitro, this composite hydrogel could significantly improve the osteogenic differentiation of BMSCs and angiogenesis ability of HUVECs. In vivo, KP and QK in the GMO hydrogel demonstrated a significant synergistic effect in promoting new bone formation in rat calvaria. Overall, the KP and QK loaded GMO hydrogel was injectable and self-healing, which can be served as an efficient approach for vascularized bone regeneration via a minimally invasive approach.

Pressure distribution feature-oriented sampling for statistical analysis of supercritical airfoil aerodynamics

In the field of supercritical wing design, various principles and rules have been summarized through theoretical and experimental analyses. Compared with black-box relationships between geometry parameters and performances, quantitative physical laws about pressure distributions and performances are clearer and more beneficial to designers. With the advancement of computational fluid dynamics and computational intelligence, discovering new rules through statistical analysis on computers has become increasingly attractive and affordable. This paper proposes a novel sampling method for the statistical study on pressure distribution features and performances, so that new physical laws can be revealed. It utilizes an adaptive sampling algorithm, of which the criteria are developed based on Kullback–Leibler divergence and Euclidean distance.In this paper, the proposed method is employed to generate airfoil samples to study the relationships between the supercritical pressure distribution features and the drag divergence Mach number as well as the drag creep characteristic. Compared with conventional sampling methods, the proposed method can efficiently distribute samples in the pressure distribution feature space rather than directly sampling airfoil geometry parameters. The corresponding geometry parameters are searched and found under constraints, so that supercritical airfoil samples that are well distributed in the pressure distribution space are obtained. These samples allow statistical studies to obtain more reliable and universal aerodynamic rules that can be applied to supercritical airfoil designs.