Ua tsaug rau koj tuaj xyuas Nature.com.Koj siv lub browser version nrog kev txhawb nqa CSS tsawg.Rau qhov kev paub zoo tshaj plaws, peb xav kom koj siv qhov browser tshiab (lossis lov tes taw Compatibility Hom hauv Internet Explorer).Tsis tas li ntawd, txhawm rau xyuas kom muaj kev txhawb nqa tsis tu ncua, peb qhia lub vev xaib tsis muaj qauv thiab JavaScript.
Qhia ib lub carousel ntawm peb slides ib zaug.Siv cov nyees khawm dhau los thiab Tom ntej kom txav mus los ntawm peb qhov swb ib zaug, lossis siv cov khawm slider thaum kawg kom txav mus los ntawm peb qhov swb ib zaug.
Nws tau tsis ntev los no tau pom tias kev siv ultrasound tuaj yeem txhim kho cov ntaub so ntswg tawm hauv ultrasound-enhanced fine needle aspiration biopsy (USeFNAB) piv rau cov pa zoo koob aspiration biopsy (FNAB).Kev sib raug zoo ntawm bevel geometry thiab koob tip action tseem tsis tau tshawb nrhiav.Hauv txoj kev tshawb no, peb tau tshawb xyuas cov khoom ntawm rab koob resonance thiab deflection amplitude rau ntau yam koob bevel geometries nrog txawv bevel lengths.Siv cov lancet zoo ib yam nrog kev txiav 3.9 hli, lub taub hau deflection fais fab (DPR) yog 220 thiab 105 µm / W hauv huab cua thiab dej, feem.Qhov no yog siab tshaj qhov axisymmetric 4mm bevel taub, uas ua tiav DPR ntawm 180 thiab 80 µm / W hauv huab cua thiab dej, feem.Txoj kev tshawb no qhia txog qhov tseem ceeb ntawm kev sib raug zoo ntawm kev khoov qhov tawv ntawm lub bevel geometry nyob rau hauv cov ntsiab lus ntawm cov khoom siv sib txawv, thiab yog li yuav muab kev nkag siab rau hauv txoj hauv kev los tswj kev txiav txim tom qab puncture los ntawm kev hloov cov koob bevel geometry, uas yog ib qho tseem ceeb rau USeFNAB.Daim ntawv thov tseem ceeb.
Fine needle aspiration biopsy (FNAB) yog ib qho txheej txheem uas siv rab koob kom tau txais cov qauv ntawm cov ntaub so ntswg thaum xav tias muaj qhov txawv txav 1,2,3.Cov lus qhia hom Franseen tau pom tias muab kev kuaj mob ntau dua li cov lus qhia Lancet4 thiab Menghini5 ib txwm muaj.Axisymmetric (piv txwv li circumferential) bevels kuj tau npaj siab los ua kom muaj qhov ua tau zoo ntawm tus qauv tsim nyog rau histopathology6.
Thaum lub sij hawm biopsy, ib rab koob yog dhau los ntawm cov khaubncaws sab nraud povtseg ntawm daim tawv nqaij thiab cov ntaub so ntswg los qhia qhov tsis txaus ntseeg pathology.Cov kev tshawb fawb tsis ntev los no tau pom tias kev ua kom ultrasonic tuaj yeem txo qhov kev quab yuam kom nkag mus rau cov ntaub so ntswg 7,8,9,10.Needle bevel geometry tau pom tias muaj kev cuam tshuam rau rab koob sib cuam tshuam, piv txwv li ntev bevels tau pom tias muaj cov ntaub so ntswg nkag mus rau qis dua 11 .Nws tau raug pom zoo tias tom qab rab koob tau nkag mus rau hauv cov ntaub so ntswg, piv txwv li, tom qab puncture, txiav quab yuam ntawm rab koob yuav yog 75% ntawm tag nrho cov koob-cov ntaub so ntswg sib cuam tshuam force12.Ultrasound (Tebchaws Asmeskas) tau pom tias yuav txhim kho qhov zoo ntawm kev kuaj mob nqaij mos biopsy nyob rau tom qab puncture phase13.Lwm txoj hauv kev los txhim kho pob txha biopsy tau tsim rau cov ntaub so ntswg nyuaj sampling14,15 tab sis tsis muaj cov txiaj ntsig tau tshaj tawm tias txhim kho biopsy zoo.Ntau qhov kev tshawb fawb tseem pom tau tias kev hloov pauv hloov pauv tau nce ntxiv nrog kev nce qib ntawm kev tsav tsheb ultrasonic voltage 16,17,18.Txawm hais tias muaj ntau yam kev tshawb fawb ntawm axial (longitudinal) static rog hauv koob-cov ntaub so ntswg kev sib cuam tshuam19,20, kev tshawb fawb ntawm lub cev nqaij daim tawv thiab rab koob bevel geometry hauv ultrasonic enhanced FNAB (USeFNAB) raug txwv.
Lub hom phiaj ntawm txoj kev tshawb no yog los tshawb xyuas cov txiaj ntsig ntawm qhov sib txawv bevel geometries ntawm koob tip nkaus uas tau tsav los ntawm rab koob flexion ntawm ultrasonic frequencies.Tshwj xeeb, peb tau tshawb xyuas cov txiaj ntsig ntawm kev txhaj tshuaj nruab nrab ntawm rab koob tip deflection tom qab puncture rau cov pa koob bevels (xws li, lancets), axisymmetric thiab asymmetric ib leeg bevel geometries (Daim duab. nkag mus los yog cov nqaij mos nuclei.
Ntau yam bevel geometry tau suav nrog hauv txoj kev tshawb no.(a) Lancets ua raws li ISO 7864: 201636 qhov twg \(\alpha\) yog thawj bevel kaum sab xis, \(\theta\) yog lub thib ob bevel tig lub kaum sab xis, thiab \(\phi\) yog lub thib ob bevel tig lub kaum sab xis degrees, nyob rau hauv degrees (\(^\circ\)).(b) linear asymmetrical ib kauj ruam chamfers (hu ua "standard" hauv DIN 13097: 201937) thiab (c) linear axisymmetric (circumferential) ib kauj ruam chamfers.
Peb txoj hauv kev yog los ua qauv thawj qhov kev hloov pauv ntawm qhov khoov wavelength raws txoj kab nqes rau cov qauv lancet, axisymmetric, thiab asymmetric ib-theem nqes hav geometries.Peb mam li xam qhov kev tshawb fawb parametric los tshuaj xyuas cov nyhuv ntawm lub kaum sab xis thiab lub raj ntev ntawm kev thauj mus los ntawm kev txav mus los.Qhov no yog ua los txiav txim siab qhov ntev ntev rau kev ua tus qauv koob.Raws li kev simulation, rab koob prototypes tau tsim thiab lawv tus cwj pwm resonant hauv huab cua, dej, thiab 10% (w / v) ballistic gelatin tau sim ua kom pom tseeb los ntawm kev ntsuas qhov ntsuas hluav taws xob coefficient thiab suav cov hluav taws xob hloov hluav taws xob, los ntawm kev ua haujlwm zaus. txiav txim siab..Thaum kawg, kev ntsuas kev kub ceev yog siv los ntsuas qhov deflection ntawm qhov khoov nthwv dej ntawm qhov kawg ntawm rab koob hauv huab cua thiab dej, thiab kwv yees lub zog hluav taws xob xa mus los ntawm txhua qhov qaij thiab qhov deflection fais fab xwm txheej (DPR) geometry ntawm cov tshuaj txhaj. nruab nrab.
Raws li pom nyob rau hauv daim duab 2a, siv No. 21 yeeb nkab (0.80 mm OD, 0.49 mm ID, 0.155 mm yeeb nkab phab ntsa thickness, txheem phab ntsa raws li teev nyob rau hauv ISO 9626: 201621) ua los ntawm 316 stainless hlau (Young's modulus 205).\(\text {GN/m}^{2}\), density 8070 kg/m\(^{3}\), Poisson's ratio 0.275).
Kev txiav txim siab ntawm qhov khoov wavelength thiab tuning ntawm finite element qauv (FEM) ntawm rab koob thiab ciam teb tej yam kev mob.(a) Kev txiav txim siab ntawm bevel length (BL) thiab kav ntev (TL).(b) Peb-dimensional (3D) finite element qauv (FEM) siv harmonic point force \(\tilde{F}_y\vec{j}\) ua kom lub koob ntawm qhov kawg, deflect qhov taw tes, thiab ntsuas qhov nrawm per tip (\( \tilde{u}_y\vec {j}\), \(\tilde{v}_y\vec {j}\))) los laij cov tsheb thauj mus los.\(\lambda _y\) txhais tau tias yog bending wavelength txuam nrog lub zog ntsug \(\tilde{F}_y\vec {j}\).(c) Txiav txim siab qhov nruab nrab ntawm lub ntiajteb txawj nqus, ntu ntu A, thiab lub sijhawm ntawm inertia \(I_{xx}\) thiab \(I_{yy}\) nyob ib ncig ntawm x-axis thiab y-axis raws li.
Raws li qhia hauv daim duab.2b, c, rau ib qho infinite (infinite) beam nrog cross-sectional cheeb tsam A thiab ntawm ib tug loj wavelength piv rau qhov luaj li cas ntawm tus ntoo khaub lig-section ntawm lub beam, lub dabtsi yog khoov (los yog dabtsi yog khoov) theem tshaj tawm \(c_{EI}\ ) yog txhais raws li 22:
qhov twg E yog Young's modulus (\(\text {N/m}^{2}\)), \(\omega _0 = 2\pi f_0\) is the excitation angular zaus (rad/s), where \( f_0 \ ) yog linear zaus (1/s los yog Hz), Kuv yog lub sij hawm ntawm inertia ntawm cheeb tsam nyob ib ncig ntawm lub axis ntawm paj \((\text {m}^{4})\) thiab \(m'=\ rho _0 A \) yog qhov loj ntawm chav tsev ntev (kg/m), qhov twg \(\rho _0\) yog qhov ceev \((\text {kg/m}^{3})\) thiab A yog tus ntoo khaub lig -sectional area of the beam (xy plane) (\ (\text {m}^{2}\)).Txij li thaum nyob rau hauv peb cov ntaub ntawv cov ntaub ntawv thov quab yuam yog parallel mus rau ntsug y-axis, piv txwv li \(\tilde{F}_y\vec {j}\), peb tsuas yog txaus siab rau lub sij hawm ntawm inertia ntawm cheeb tsam ib ncig ntawm kab rov tav x- axis, ie \(I_{xx} \), so:
Rau cov qauv finite element (FEM), qhov kev sib haum xeeb dawb huv (m) yog assumed, yog li qhov acceleration (\(\text {m/s}^{2}\)) yog qhia li \(\partial ^2 \vec { u}/ \ partial t^2 = -\omega ^2\vec {u}\), eg \(\vec {u}(x, y, z, t)) := u_x\vec {i} + u_y \vec {j }+ u_z\vec {k}\) yog peb-dimensional displacement vector txhais nyob rau hauv spatial coordinates.Hloov cov tom kawg nrog rau qhov kawg deformable Lagrangian daim ntawv ntawm lub zog sib npaug txoj cai23, raws li nws qhov kev siv hauv COMSOL Multiphysics software pob (versions 5.4-5.5, COMSOL Inc., Massachusetts, USA), muab:
Where \(\vec {\nabla}:= \frac{\partial}}{\partial x}\vec {i} + \frac{\partial}}{\partial y}\vec {j} + \frac{ \partial }{\partial z}\vec {k}\) is the tensor divergence operator, and \({\underline{\sigma}}\) is the second Piola-Kirchhoff stress tensor (thib ob, \(\text { N /m}^{2}\)), and \(\vec {F_V}:= F_{V_x}\vec {i}+ F_{V_y}\vec {j}+ F_{V_z}\vec { k} \) yog vector ntawm lub cev quab yuam (\(\text {N/m}^{3}\)) ntawm txhua deformable ntim, thiab \(e^{j\phi }\) yog theem ntawm cov lub cev quab yuam, muaj lub kaum sab xis \(\phi\) (rad).Nyob rau hauv peb cov ntaub ntawv, lub ntim quab yuam ntawm lub cev yog xoom, thiab peb cov qauv assumes geometric linearity thiab me me purely elastic deformations, piv txwv li \({\underline{\varepsilon}}^{el} = {\underline{\varepsilon}}\ ), qhov twg \({\underline{\varepsilon}}^{el}\) thiab \({\underline{ \varepsilon}}\) - elastic deformation thiab tag nrho deformation (dim tsis muaj qhov thib ob qhov kev txiav txim), feem.Hooke's constitutive isotropic elasticity tensor \(\underline {\underline {C))\) yog tau siv Young's modulus E(\(\text{N/m}^{2}\)) thiab Poisson's ratio v yog txhais, yog li ntawd \(\underline{\underline{C}}:=\underline{\underline{C}}(E,v)\) (fourth order).Yog li qhov kev ntsuas kev ntxhov siab dhau los ua \({\underline{\sigma}} := \underline{\underline{C}}:\underline{\varepsilon}}\).
Cov kev suav tau ua nrog 10-node tetrahedral ntsiab nrog lub ntsiab loj \(\le\) 8 μm.Lub koob yog ua qauv hauv lub tshuab nqus tsev, thiab tus nqi hloov pauv hloov tshuab (ms-1 H-1) txhais tau tias yog \(|\tilde{Y}_{v_yF_y}|= |\tilde{v}_y\vec {j} |/|\ tilde{F}_y\vec {j}|\)24, where \(\tilde{v}_y\vec {j}\) yog cov zis complex tshaj tawm ntawm tes, thiab \( \tilde{ F} _y\vec {j }\) yog lub zog tsav nyuaj nyob rau ntawm qhov kawg ntawm lub raj, raws li qhia hauv daim duab 2b.Transmissive mechanical mobility yog qhia hauv decibels (dB) siv tus nqi siab tshaj plaws raws li kev siv, piv txwv li \(20\log _{10} (|\tilde{Y}|/ |\tilde{Y}_{max}| )\ ), Tag nrho cov kev tshawb fawb FEM tau ua tiav ntawm qhov zaus ntawm 29.75 kHz.
Tus qauv tsim ntawm rab koob (Daim duab 3) muaj cov qauv 21 gauge hypodermic koob (catalog naj npawb: 4665643, Sterican\(^\circledR\), nrog rau sab nraud txoj kab uas hla ntawm 0.8 hli, ntev 120 hli, ua los ntawm AISI chromium-nickel stainless hlau 304., B. Braun Melsungen AG, Melsungen, Lub teb chaws Yelemees) muab ib lub hnab yas Luer Xauv lub tes tsho ua los ntawm polypropylene proximal nrog kev hloov pauv hloov pauv.Lub koob raj yog soldered rau lub waveguide raws li qhia nyob rau hauv daim duab 3b.Lub waveguide tau luam tawm ntawm lub tshuab luam ntawv stainless hlau 3D (EOS Stainless Steel 316L ntawm EOS M 290 3D tshuab luam ntawv, 3D Formtech Oy, Jyväskylä, Finland) thiab tom qab ntawd txuas rau Langevin sensor siv M4 bolts.Lub Langevin transducer muaj 8 lub nplhaib piezoelectric nrog ob qhov hnyav ntawm txhua qhov kawg.
Plaub hom lus qhia (daim duab), ib lub lag luam muaj lancet (L), thiab peb tsim axisymmetric ib-theem bevels (AX1-3) yog tus cwj pwm los ntawm bevel lengths (BL) ntawm 4, 1.2, thiab 0.5 hli, raws li.(a) Close-up ntawm lub tiav koob taub hau.(b) Sab saum toj saib ntawm plaub tus pins soldered rau 3D luam tawm waveguide thiab tom qab ntawd txuas nrog Langevin sensor nrog M4 bolts.
Peb axisymmetric bevel tswv yim (Fig. 3) (TAs Tshuab cuab yeej Oy) tau tsim nrog bevel lengths (BL, txiav txim siab nyob rau hauv daim duab 2a) ntawm 4.0, 1.2 thiab 0.5 mm, sib xws rau \(\approx\) 2\ (^\ circ\), 7\(^\circ\) and 18\(^\circ\).Lub waveguide thiab stylus hnyav yog 3.4 ± 0.017 g (txhais tau tias ± SD, n = 4) rau bevel L thiab AX1–3, raws li (Quintix\(^\circledR\) 224 Design 2, Sartorius AG, Göttingen, Germany).Tag nrho qhov ntev ntawm qhov kawg ntawm rab koob mus rau qhov kawg ntawm lub tes tsho yas yog 13.7, 13.3, 13.3, 13.3 cm rau bevel L thiab AX1-3 hauv daim duab 3b, raws li.
Rau tag nrho cov kev teeb tsa rab koob, qhov ntev ntawm qhov kawg ntawm rab koob mus rau qhov kawg ntawm lub waveguide (piv txwv li, thaj chaw soldering) yog 4.3 cm, thiab lub koob raj yog taw qhia kom lub bevel tig mus (piv txwv li, mus txog rau Y axis. ).), raws li nyob rau hauv (Fig. 2).
Ib tsab ntawv kev cai hauv MATLAB (R2019a, The MathWorks Inc., Massachusetts, USA) uas khiav ntawm lub khoos phis tawj (Latitude 7490, Dell Inc., Texas, USA) tau siv los tsim cov kab tawm sinusoidal cheb ntawm 25 txog 35 kHz hauv 7 vib nas this, hloov mus rau lub teeb liab analog los ntawm digital-to-analog (DA) converter (Analog Discovery 2, Digilent Inc., Washington, USA).Lub teeb liab analog \(V_0\) (0.5 Vp-p) yog ces amplified nrog ib tug tshwj xeeb xov tooj cua zaus (RF) amplifier (Mariachi Oy, Turku, Finland).Qhov poob ntawm lub zog amplifying \({V_I}\) yog cov zis tawm los ntawm RF amplifier nrog cov zis impedance ntawm 50 \(\Omega\) mus rau lub transformer ua rau hauv lub koob qauv nrog input impedance ntawm 50 \(\Omega)\) Langevin transducer (pem hauv ntej thiab nram qab multilayer piezoelectric transducers, loaded nrog huab hwm coj) yog siv los tsim cov tshuab tsis muaj zog.Kev cai RF amplifier yog nruab nrog dual-channel sawv nthwv dej zog qhov ntsuas (SWR) ntsuas uas tuaj yeem ntes qhov xwm txheej \({V_I}\) thiab cuam tshuam qhov hluav taws xob loj \(V_R\) dhau ntawm 300 kHz analog-to-digital (AD ) converter (Analog Discovery 2).Lub teeb liab excitation yog amplitude modulated thaum pib thiab thaum kawg kom tsis txhob overloading lub amplifier input nrog transients.
Siv cov ntawv kev cai siv nyob rau hauv MATLAB, zaus teb muaj nuj nqi (AFC), piv txwv li assumes ib tug linear nyob ruaj ruaj system.Tsis tas li ntawd, siv 20 mus rau 40 kHz band pass lim kom tshem tawm cov tsis xav tau ntau zaus ntawm lub teeb liab.Xa mus rau kev xa xov kab txoj kev xav, \(\tilde{H}(f)\) nyob rau hauv cov ntaub ntawv no yog sib npaug rau qhov voltage reflection coefficient, piv txwv li \(\rho _{V} \equiv {V_R}/{V_I} \)26 Txij li thaum cov zis impedance ntawm lub amplifier \(Z_0\) sib raug rau cov input impedance ntawm lub built-in transformer ntawm lub converter, thiab lub reflection coefficient ntawm hluav taws xob fais fab \({P_R}/{P_I}\) raug txo mus rau \ ({V_R }^2/{V_I}^2\ ), then is \(|\rho _{V}|^2\).Nyob rau hauv rooj plaub uas tus nqi kiag li ntawm hluav taws xob yuav tsum tau, xam qhov xwm txheej \(P_I\) thiab reflected \(P_R\) lub hwj chim (W) los ntawm kev noj lub hauv paus txhais tau tias square (rms) tus nqi ntawm cov coj voltage, piv txwv li, rau txoj kab sib kis nrog sinusoidal excitation, \(P = {V}^2/(2Z_0)\)26, qhov twg \(Z_0\) sib npaug 50 \(\Omega\).Lub zog hluav taws xob xa mus rau qhov load \(P_T\) (piv txwv li qhov nruab nrab nruab nrab) tuaj yeem suav tau raws li \(|P_I – P_R |\) (W RMS) thiab lub zog hloov pauv hluav taws xob (PTE) tuaj yeem txhais tau tias yog feem pua (%) yog li muab 27:
Tom qab ntawd cov lus teb zaus yog siv los kwv yees cov zaus zaus \(f_{1-3}\) (kHz) ntawm tus qauv stylus thiab cov khoom siv hluav taws xob sib txuas, \(\text {PTE}_{1{-}3} \ .FWHM (\(\text {FWHM}_{1{-}3}\), Hz) yog kwv yees ncaj qha los ntawm \(\text {PTE}_{1{-}3}\), los ntawm Table 1 frequencies \(f_{1-3}\) piav nyob rau hauv .
Ib txoj hauv kev los ntsuas qhov zaus teb (AFC) ntawm cov qauv acicular.Dual-channel swept-sine ntsuas25,38 yog siv kom tau txais cov lus teb zaus \(\tilde{H}(f)\) thiab nws cov lus teb impulse H(t).\({\mathcal {F}}\) and \({\mathcal {F}}^{-1}\) denote the numerical truncated Fourier transform and the inverse transform operation, ntsig.\(\tilde{G}(f)\) txhais tau tias ob lub teeb liab tau muab faib ua ntau zaus, xws li \(\tilde{G}_{XrX}\) txhais tau tias inverse scan\(\tilde{X} r( f )\) thiab voltage poob teeb liab \(\tilde{X}(f)\).
Raws li qhia hauv daim duab.5, lub koob yees duab ceev ceev (Phantom V1612, Vision Research Inc., New Jersey, USA) nruab nrog lub lens macro (MP-E 65mm, \(f) / 2.8, 1-5 \ (\times\), Canon Inc .., Tokyo, Nyiv) tau siv los sau cov deflection ntawm ib rab koob taub hau raug flexural excitation (ib zaus, nruam sinusoid) ntawm ib zaus ntawm 27.5-30 kHz.Txhawm rau tsim daim duab duab ntxoov ntxoo, lub caij txias ntawm lub siab siv dawb LED (ib feem naj npawb: 4052899910881, White Led, 3000 K, 4150 lm, Osram Opto Semiconductors GmbH, Regensburg, Lub teb chaws Yelemees) tau muab tso rau hauv qab ntawm lub koob.
Saib pem hauv ntej ntawm kev sim teeb tsa.Qhov tob yog ntsuas los ntawm qhov chaw xov xwm.Cov qauv koob yog clamped thiab mounted ntawm lub rooj tsav tsheb hloov tsheb.Siv lub koob yees duab ceev ceev nrog lub lens loj (5\(\times\)) los ntsuas qhov deflection ntawm lub taub hau beveled.Tag nrho qhov ntev yog nyob rau hauv millimeters.
Rau txhua hom koob bevel, peb tau sau 300 lub koob yees duab ceev ceev ntawm 128 \(\x\) 128 pixels, txhua qhov kev daws teeb meem ntawm 1/180 mm (\(\ approx) 5 µm), nrog rau kev daws teeb meem ntawm lub cev. ntawm 310,000 ntas ib ob.Raws li pom nyob rau hauv daim duab 6, txhua tus ncej (1) yog cropped (2) kom lub ntsis yog nyob rau hauv lub xeem kab (hauv qab) ntawm tus ncej, thiab ces tus histogram ntawm daim duab (3) yog xam, ces Canny pib 1 thiab 2 tuaj yeem txiav txim siab.Tom qab ntawd siv Canny28(4) ntug kev tshawb nrhiav siv Sobel tus neeg teb xov tooj 3 \(\times\) 3 thiab suav cov pixel txoj hauj lwm ntawm cov tsis-cavitational hypotenuse (labeled \(\mathbf {\times }\)) rau tag nrho 300-fold cov kauj ruam .Txhawm rau txiav txim siab qhov ntev ntawm qhov deflection thaum kawg, qhov derivative yog xam (siv lub hauv paus sib txawv algorithm) (6) thiab cov ncej uas muaj cov hauv zos extrema (piv txwv li ncov) ntawm deflection (7) raug txheeb xyuas.Tom qab pom qhov pom ntawm qhov tsis-cavitating ntug, ib khub ntawm thav ntawv (los yog ob lub thav duab sib cais los ntawm ib nrab ntawm lub sijhawm) (7) raug xaiv thiab lub ntsis deflection ntsuas (labeled \(\mathbf {\times} \ ) Cov saum toj no tau siv. hauv Python (v3.8, Python Software Foundation, python.org) siv OpenCV Canny edge detection algorithm (v4.5.1, qhib lub khoos phis tawj tsis pom kev, opencv.org). hluav taws xob \ (P_T \) (W, rms) .
Lub tswv yim deflection tau ntsuas los ntawm kev siv cov thav duab los ntawm lub koob yees duab ceev ntawm 310 kHz siv 7-kauj ruam algorithm (1-7) suav nrog framing (1-2), Canny edge detection (3-4), pixel qhov chaw ntug xam (5) thiab lawv lub sij hawm derivatives (6), thiab thaum kawg ncov-rau-peak tip deflection raug ntsuas ntawm visually soj ntsuam khub ntawm thav ntawv (7).
Kev ntsuas tau muab tso rau hauv huab cua (22.4-22.9 ° C), dej deionized (20.8-21.5 ° C) thiab ballistic gelatin 10% (w/v) (19.7-23.0 ° C, \(\text {Honeywell}^{ \text { TM}}\) \(\text {Fluka}^{\text {TM}}\) Bovine and Pork Bone Gelatin for Type I Ballistic Analysis, Honeywell International, North Carolina, USA).Kev ntsuas kub tau ntsuas nrog K-hom thermocouple amplifier (AD595, Analog Devices Inc., MA, USA) thiab K-hom thermocouple (Fluke 80PK-1 Bead Probe No. 3648 type-K, Fluke Corporation, Washington, USA).Los ntawm qhov nruab nrab Qhov tob yog ntsuas los ntawm qhov chaw (teeb tsa raws li lub hauv paus chiv keeb ntawm z-axis) siv lub ntsug motorized z-axis theem (8MT50-100BS1-XYZ, Standa Ltd., Vilnius, Lithuania) nrog kev daws teeb meem ntawm 5 µm.rau kauj ruam.
Txij li cov qauv loj me me (n = 5) thiab qhov qub tsis tuaj yeem xav tau, ib qho piv txwv ob-tailed Wilcoxon rank sum test (R, v4.0.3, R Foundation for Statistical Computing, r-project .org) tau siv. los sib piv tus nqi ntawm variance koob taub rau txawv bevels.Muaj 3 qhov kev sib piv rau ib txoj kab nqes, yog li kev kho Bonferroni tau siv nrog kev hloov kho qhov tseem ceeb ntawm 0.017 thiab qhov yuam kev ntawm 5%.
Cia peb tam sim no tig mus rau Fig.7.Ntawm qhov zaus ntawm 29.75 kHz, khoov ib nrab-yoj (\(\lambda_y/2\)) ntawm 21-gauge koob yog \(\ kwv yees) 8 hli.Raws li ib tug mus rau lub ntsis, lub bending wavelength txo nyob rau hauv lub oblique lub kaum sab xis.Ntawm lub ntsis \(\lambda _y/2\) \(\kwv yees\) muaj cov kauj ruam ntawm 3, 1 thiab 7 hli rau ib txwm lanceolate (a), asymmetric (b) thiab axisymmetric (c) inclination ntawm ib rab koob. , raws.Yog li, qhov no txhais tau hais tias qhov ntau ntawm lancet yog \ (\ kwv yees) 5 hli (vim qhov tseeb tias ob lub dav hlau ntawm lancet tsim ib qho point29,30), asymmetric bevel yog 7 hli, asymmetric bevel yog 1. mm.Axisymmetric slopes (qhov nruab nrab ntawm lub ntiajteb txawj nqus tseem nyob tas li, yog li tsuas yog cov yeeb nkab phab ntsa thickness tau hloov raws txoj kab nqes).
FEM kev tshawb fawb thiab kev siv cov kev sib npaug ntawm ib zaus ntawm 29.75 kHz.(1) Thaum xam qhov txawv ntawm qhov khoov ib nrab-yoj (\(\lambda_y/2\)) rau lancet (a), asymmetric (b) thiab axisymmetric (c) bevel geometries (raws li hauv daim duab 1a, b, c) )Qhov nruab nrab tus nqi \(\lambda_y/2\) ntawm lub lancet, asymmetric, thiab axisymmetric bevels yog 5.65, 5.17, thiab 7.52 mm, ntsig txog.Nco ntsoov tias cov tuab tuab rau asymmetric thiab axisymmetric bevels yog txwv rau \(\ approx) 50 µm.
Peak mobility \(|\tilde{Y}_{v_yF_y}|\) yog qhov zoo tshaj plaws ua ke ntawm raj ntev (TL) thiab bevel length (BL) (Fig. 8, 9).Rau ib tug pa lancet, txij li thaum nws loj yog tsau, qhov zoo tshaj plaws TL yog \(\ approximately) 29.1 hli (Fig. 8).Rau asymmetric thiab axisymmetric bevels (Fig. 9a, b, ntsig txog), FEM cov kev tshawb fawb suav nrog BL ntawm 1 txog 7 hli, yog li qhov zoo tshaj plaws TL yog los ntawm 26.9 mus rau 28.7 mm (ntau 1.8 mm) thiab los ntawm 27.9 txog 29 .2 mm (ntau 1.3mm), raws.Rau qhov asymmetric nqes hav (Fig. 9a), qhov zoo tshaj plaws TL nce linearly, mus txog lub toj siab ntawm BL 4 hli, thiab ces sharply txo los ntawm BL 5 mus rau 7 hli.Rau ib qho axisymmetric bevel (Fig. 9b), qhov zoo tshaj plaws TL nce linearly nrog nce BL thiab thaum kawg stabilized ntawm BL ntawm 6 mus rau 7 hli.Kev tshawb fawb txuas ntxiv ntawm axisymmetric qaij (Fig. 9c) tau nthuav tawm cov txheej txheem sib txawv ntawm qhov zoo tshaj plaws TLs ntawm \(\approx) 35.1–37.1 hli.Rau txhua BLs, qhov kev ncua deb ntawm ob qhov zoo tshaj plaws TLs yog \(\approx\) 8mm (sib npaug rau \(\lambda_y/2\)).
Lancet kis tau tus mob ntawm 29.75 kHz.Lub koob tau hloov pauv tau zoo siab ntawm qhov zaus ntawm 29.75 kHz thiab kev vibration tau ntsuas ntawm qhov kawg ntawm rab koob thiab qhia tias tus nqi ntawm cov khoom siv sib kis tau (dB txheeb ze rau tus nqi siab tshaj) rau TL 26.5-29.5 mm (hauv 0.1 mm increments) .
Cov kev tshawb fawb Parametric ntawm FEM ntawm qhov zaus ntawm 29.75 kHz qhia tau hais tias qhov kev hloov pauv ntawm lub taub axisymmetric tsis tshua cuam tshuam los ntawm kev hloov pauv ntawm qhov ntev ntawm lub raj dua li nws cov asymmetric counterpart.Bevel length (BL) thiab cov yeeb nkab ntev (TL) kev tshawb fawb ntawm asymmetric (a) thiab axisymmetric (b, c) bevel geometries nyob rau hauv lub zaus domain kawm siv FEM ( ciam teb tej yam kev mob yog qhia nyob rau hauv daim duab 2).(a, b) TL ranged ntawm 26.5 mus rau 29.5 hli (0.1 hli kauj ruam) thiab BL 1–7 hli (0.5 hli kauj ruam).(c) Extended axisymmetric tilt kev tshawb fawb suav nrog TL 25-40 mm (hauv 0.05 mm increments) thiab BL 0.1–7 mm (hauv 0.1 mm increments) qhia tias \(\lambda_y/2\ ) yuav tsum ua tau raws li qhov yuav tsum tau muaj ntawm lub ntsis.tsiv ciam teb tej yam kev mob.
Lub koob configuration muaj peb eigenfrequencies \(f_{1-3}\) muab faib ua low, medium and high mode regions as show in Table 1. PTE size was recorded as displayed in fig.10 thiab tom qab ntawd txheeb xyuas hauv daim duab 11. Hauv qab no yog cov kev tshawb pom rau txhua qhov chaw modal:
Cov ntawv sau tam sim no lub zog hloov hluav taws xob (PTE) amplitudes tau txais nrog swept-frequency sinusoidal excitation rau lancet (L) thiab axisymmetric bevel AX1-3 hauv huab cua, dej thiab gelatin ntawm qhov tob ntawm 20 hli.Ib sab spectra yog qhia.Qhov ntsuas zaus teb (piv txwv li ntawm 300 kHz) yog qhov qis dhau lim thiab tom qab ntawd ntsuas los ntawm qhov ntsuas ntawm 200 rau kev tshuaj ntsuam xyuas.Lub teeb liab-rau-nruab piv yog \(\le\) 45 dB.PTE theem (cov kab liab dotted) tau qhia hauv qib (\(^{\circ}\)).
Lub modal teb tsom xam (txhais tau tias ± tus qauv sib txawv, n = 5) qhia hauv daim duab 10, rau qhov chaw nqes L thiab AX1-3, hauv huab cua, dej thiab 10% gelatin (qhov tob 20 mm), nrog (sab saum toj) peb thaj tsam modal ( qis, nruab nrab thiab siab) thiab lawv qhov sib thooj modal frequencies\(f_{1-3 }\) (kHz), (nruab nrab) lub zog efficiency \(\text {PTE}_{1{-}3}\) xam siv qhov sib npaug .(4) thiab (hauv qab) dav dav ntawm ib nrab qhov siab tshaj qhov ntsuas \(\text {FWHM}_{1{-}3}\) (Hz), feem.Nco ntsoov tias qhov kev ntsuas bandwidth raug hla thaum PTE qis tau sau npe, piv txwv li \(\text {FWHM}_{1}\) nyob rau hauv rooj plaub ntawm AX2 txoj kab nqes.Qhov \(f_2\) hom tau pom tias yog qhov tsim nyog tshaj plaws rau kev sib piv cov nqes hav deflections, raws li nws pom qhov siab tshaj plaws ntawm lub zog hloov hluav taws xob (\(\text {PTE}_{2}\)), mus txog 99%.
Thawj thaj tsam modal: \(f_1\) tsis nyob ntawm ntau yam ntawm qhov nruab nrab tso, tab sis nyob ntawm qhov geometry ntawm txoj kab nqes.\(f_1\) txo qis nrog txo bevel ntev (27.1, 26.2 thiab 25.9 kHz nyob rau hauv huab cua rau AX1-3, ntsig txog).Cov cheeb tsam nruab nrab \(\text {PTE}_{1}\) thiab \(\text {FWHM}_{1}\) yog \(\approx\) 81% thiab 230 Hz feem.\(\text {FWHM}_{1}\) muaj cov ntsiab lus gelatin siab tshaj plaws hauv Lancet (L, 473 Hz).Nco ntsoov tias \(\text {FWHM}_{1}\) AX2 hauv gelatin tsis tuaj yeem soj ntsuam vim qhov ntsuas qis FRF amplitude.
Qhov thib ob modal cheeb tsam: \(f_2\) nyob ntawm hom xov xwm tso thiab lub bevel.Qhov nruab nrab qhov tseem ceeb \(f_2\) yog 29.1, 27.9 thiab 28.5 kHz hauv huab cua, dej thiab gelatin, feem.Lub cheeb tsam modal no kuj pom tias muaj PTE siab ntawm 99%, qhov siab tshaj plaws ntawm txhua pab pawg ntsuas, nrog rau thaj tsam nruab nrab ntawm 84%.\(\text {FWHM}_{2}\) has a regional average of \(\approximately\) 910 Hz.
Thib peb hom cheeb tsam: zaus \(f_3\) nyob ntawm hom xov xwm thiab bevel.Qhov nruab nrab \(f_3\) qhov tseem ceeb yog 32.0, 31.0 thiab 31.3 kHz hauv huab cua, dej thiab gelatin, feem.Tus \(\text {PTE}_{3}\) lub regional nruab nrab yog \(\approximately\) 74%, qhov qis tshaj ntawm ib cheeb tsam.Lub cheeb tsam nruab nrab \(\text {FWHM}_{3}\) yog \(\approximately\) 1085 Hz, uas yog siab tshaj qhov thib ib thiab thib ob cheeb tsam.
Cov hauv qab no yog hais txog Fig.12 thiab Table 2. Lub lancet (L) deflected feem ntau (nrog rau qhov tseem ceeb rau tag nrho cov lus qhia, \(p<\) 0.017) nyob rau hauv ob qho tib si huab cua thiab dej (Fig. 12a), ua tiav qhov siab tshaj plaws DPR (txog 220 µm/ W hauv huab cua). 12 thiab Table 2. Lub lancet (L) deflected feem ntau (nrog rau qhov tseem ceeb rau tag nrho cov lus qhia, \(p<\) 0.017) nyob rau hauv ob qho tib si huab cua thiab dej (Fig. 12a), ua tiav qhov siab tshaj plaws DPR (txog 220 µm/ W hauv huab cua). Следующее относится к рисунку 12 и таблице 2. Ланцет (L) отклонялся больше всего (с высокой знкьси мон высокой знкьси мон p<\) 0,017) как в воздухе, так и в воде (рис. 12а), достигая самого высокого DPR . Cov nram qab no siv tau rau daim duab 12 thiab Table 2. Lancet (L) deflected feem ntau (nrog qhov tseem ceeb tshaj plaws rau txhua lub tswv yim, \(p<\) 0.017) nyob rau hauv ob qho tib si huab cua thiab dej (Fig. 12a), ua tiav qhov siab tshaj plaws DPR .(txog 220 μm / W hauv huab cua).Smt.Daim duab 12 thiab Table 2 hauv qab no.柳叶刀(L) 在空气和水中偏转最多（对所有尖端具有高显着性，\(p<\) 在 0.017）（图12a），地穞220 µm/W).柳叶刀(L) muaj qhov siab tshaj plaws deflection hauv huab cua thiab dej (对所记尖端可以高电影性,\(p<\) 0.017) (图12a), thiab ua tiav qhov siab tshaj DPR (txog 220 µm / W huab cua). Ланцет (L) отклонялся больше всего (высокая значимость для всех наконечников, \(p<\) 0,017) в воздвухе (2 датигоя и большего DPR (до 220 мкм/Вт в воздухе). Lancet (L) deflected feem ntau (qhov tseem ceeb tshaj plaws rau txhua lub tswv yim, \(p<\) 0.017) nyob rau hauv huab cua thiab dej (Fig. 12a), mus txog qhov siab tshaj plaws DPR (txog 220 µm / W hauv huab cua). Hauv huab cua, AX1 uas muaj siab dua BL, deflected siab dua AX2–3 (nrog qhov tseem ceeb, \(p<\) 0.017), thaum AX3 (uas muaj qis tshaj BL) deflected ntau tshaj AX2 nrog DPR ntawm 190 µm / W. Hauv huab cua, AX1 uas muaj siab dua BL, deflected siab dua AX2–3 (nrog qhov tseem ceeb, \(p<\) 0.017), thaum AX3 (uas muaj qis tshaj BL) deflected ntau tshaj AX2 nrog DPR ntawm 190 µm / W. В воздухе AX1 с более высоким BL отклонялся выше, чем AX2–3 (со значимостью \(p<\) 0,017), тогда калсялникоты AX3 (смоты я больше, чем AX2 с DPR 190 мкм/Вт. Hauv huab cua, AX1 nrog siab dua BL deflected siab dua AX2-3 (nrog qhov tseem ceeb \(p<\) 0.017), whereas AX3 (nrog qis tshaj BL) deflected ntau tshaj AX2 nrog DPR 190 µm / W.在空气中，具有更高BL的AX1比AX2-3 偏转更高（具有显着性，\(p<\) 0.017），而AX3（具有最低BL）的偎0µm . Hauv huab cua, qhov deflection ntawm AX1 nrog siab dua BL yog siab dua li ntawm AX2-3 (qhov tseem ceeb, \(p<\) 0.017), thiab deflection ntawm AX3 (nrog qis tshaj BL) ntau dua li ntawm AX2, DPR yog 190 µm/W. В воздухе AX1 с более высоким BL отклоняется больше, чем AX2-3 (значимо, \(p<\) 0,017), тогда как AX3 (с ) смота как AX3 (с ) больше, чем AX2 с DPR 190 мкм/Вт. Hauv huab cua, AX1 nrog siab dua BL deflects ntau dua AX2-3 (tseem ceeb, \(p<\) 0.017), whereas AX3 (nrog qis tshaj BL) deflects ntau tshaj AX2 nrog DPR 190 µm / W.Ntawm 20 hli dej, qhov deflection thiab PTE AX1–3 tsis txawv txav (\(p>\) 0.017).Cov theem ntawm PTE hauv dej (90.2–98.4%) feem ntau siab dua hauv huab cua (56–77.5%) (Fig. 12c), thiab qhov tshwm sim ntawm cavitation tau sau tseg thaum lub sijhawm sim hauv dej (Daim duab 13, saib ntxiv. cov ntaub ntawv).
Tus nqi ntawm lub taub deflection (txhais tau tias ± SD, n = 5) ntsuas rau bevel L thiab AX1-3 hauv huab cua thiab dej (qhov tob 20 hli) qhia tau hais tias cov nyhuv ntawm kev hloov bevel geometry.Cov kev ntsuas tau tau siv tas li ib zaus sinusoidal excitation.(a) Peak to peak deviation (\(u_y\vec {j}\))) ntawm lub ntsis, ntsuas ntawm (b) lawv qhov sib txawv modal frequencies \(f_2\).(c) Kev hloov hluav taws xob hloov hluav taws xob (PTE, RMS, %) ntawm qhov sib npaug.(4) thiab (d) Deflection power factor (DPR, µm/W) xam raws li kev sib txawv ntawm lub ncov-rau-peak thiab xa hluav taws xob hluav taws xob \(P_T\) (Wrms).
Lub koob yees duab siab ceev nrawm duab ntxoov ntxoo qhia txog qhov sib txawv ntawm qhov siab tshaj plaws (ntsuab thiab liab dotted kab) ntawm lub lancet (L) thiab axisymmetric tip (AX1-3) hauv dej (20 hli qhov tob) dhau ib nrab lub voj voog.cycle, ntawm excitation zaus \(f_2\) (sampling zaus 310 kHz).Cov duab ntes greyscale muaj qhov loj ntawm 128 × 128 pixels thiab pixel loj ntawm \(\ approx\) 5 µm.Cov yeeb yaj kiab tuaj yeem pom hauv cov ntaub ntawv ntxiv.
Yog li, peb tau ua qauv kev hloov pauv ntawm qhov khoov wavelength (Daim duab 7) thiab suav cov kev hloov pauv ntawm cov khoom siv sib txuas rau kev sib txuas ntawm cov yeeb nkab ntev thiab chamfer (Daim duab 8, 9) rau cov pa lancet, asymmetric thiab axisymmetric chamfers ntawm cov duab geometric.Raws li yav tas los, peb kwv yees qhov pom kev deb ntawm 43 hli (los yog \(\kwv yees) 2.75\(\lambda _y\) ntawm 29.75 kHz) los ntawm lub ntsis mus rau lub weld, raws li qhia nyob rau hauv daim duab 5, thiab ua peb axisymmetrical. bevels nrog txawv bevel lengths.Peb mam li qhia lawv tus cwj pwm zaus hauv huab cua, dej, thiab 10% (w / v) ballistic gelatin piv rau cov pa lancets (Figures 10, 11) thiab txiav txim siab hom uas haum tshaj plaws rau kev sib piv bevel deflection.Thaum kawg, peb ntsuas qhov taw qhia deflection los ntawm khoov nthwv dej hauv huab cua thiab dej ntawm qhov tob ntawm 20 hli thiab ntsuas lub zog hloov hluav taws xob (PTE, %) thiab deflection fais fab tuag (DPR, µm / W) ntawm qhov nruab nrab ntxig rau txhua qhov bevel.hom angular (Fig. 12).
Needle bevel geometry tau pom tias muaj feem cuam tshuam rau tus nqi ntawm rab koob ntxeev deflection.Lub lancet ua tiav qhov siab tshaj plaws deflection thiab qhov siab tshaj DPR piv rau axisymmetric bevel nrog qis nruab nrab deflection (Fig. 12).Lub 4 hli axisymmetric bevel (AX1) nrog lub bevel ntev tshaj plaws tau ua tiav qhov tseem ceeb tshaj plaws deflection hauv huab cua piv rau lwm cov koob axisymmetric (AX2–3) (\(p <0.017\), Table 2), tab sis tsis muaj qhov sib txawv tseem ceeb. .pom thaum koob muab tso rau hauv dej.Yog li, tsis muaj qhov zoo tshaj plaws kom muaj qhov ntev bevel ntev nyob rau hauv cov nqe lus ntawm lub ncov deflection ntawm lub ntsis.Nrog rau qhov no hauv siab, nws zoo nkaus li tias bevel geometry tau kawm hauv txoj kev tshawb no muaj kev cuam tshuam ntau dua ntawm deflection tshaj qhov ntev ntawm bevel.Qhov no tej zaum yuav yog vim dabtsi yog khoov nruj, piv txwv li nyob ntawm tag nrho cov thickness ntawm cov khoom raug khoov thiab tsim ntawm rab koob.
Hauv kev sim kev tshawb fawb, qhov loj ntawm qhov cuam tshuam flexural yoj cuam tshuam los ntawm cov ciam teb ntawm lub ntsis.Thaum lub koob taub yog muab tso rau hauv dej thiab gelatin, \(\text {PTE}_{2}\) yog \(\approximately\) 95%, thiab \(\text {PTE}_{ 2}\) yog \ (\text {PTE}_{ 2}\) cov nqi yog 73% thiab 77% rau (\text {PTE}_{1}\) thiab \(\text {PTE}_{3}\), raws li (Fig. 11).Qhov no qhia tau hais tias qhov siab tshaj plaws hloov ntawm lub zog acoustic mus rau qhov nruab nrab casting, piv txwv li dej los yog gelatin, tshwm sim ntawm \(f_2\).Cov cwj pwm zoo sib xws tau pom nyob rau hauv kev tshawb fawb yav dhau los31 uas siv cov cuab yeej yooj yim teeb tsa hauv 41-43 kHz zaus ntau yam, uas cov kws sau ntawv tau pom qhov kev vam khom ntawm qhov cuam tshuam ntawm qhov hluav taws xob coefficient ntawm cov khoom siv hluav taws xob ntawm qhov nruab nrab embedding.Qhov tob tob 32 thiab cov khoom siv kho tshuab ntawm cov ntaub so ntswg muab cov khoom siv thauj khoom ntawm rab koob thiab yog li xav tias yuav cuam tshuam rau tus cwj pwm resonant ntawm UZEFNAB.Yog li, resonance nrhiav algorithms (xws li 17, 18, 33) tuaj yeem siv los ua kom zoo dua lub zog acoustic xa los ntawm rab koob.
Simulation ntawm dabtsi yog khoov wavelengths (Daim duab 7) qhia tau hais tias lub axisymmetric tip yog structurally nruj dua (ie, nruj dua nyob rau hauv dabtsi yog khoov) tshaj lub lancet thiab asymmetric bevel.Raws li (1) thiab siv cov kev sib raug zoo-frequency paub, peb kwv yees qhov khoov nruj ntawm qhov kawg ntawm rab koob li \(\txog\) 200, 20 thiab 1500 MPa rau lancet, asymmetric thiab axial inclined dav hlau, feem.Qhov no sib raug rau \(\lambda_y\) ntawm \(\approximately\) 5.3, 1.7, thiab 14.2 mm, ntsig txog, ntawm 29.75 kHz (Fig. 7a–c).Xav txog kev nyab xeeb kev kho mob thaum lub sij hawm USeFNAB, cov nyhuv ntawm geometry ntawm cov qauv nruj ntawm lub dav hlau inclined yuav tsum raug soj ntsuam34.
Txoj kev tshawb no ntawm bevel tsis txheeb ze rau lub raj ntev (Daim duab 9) qhia tau hais tias qhov zoo tshaj plaws kis tau tus mob ntau dua rau lub asymmetric bevel (1.8 hli) dua rau lub axisymmetric bevel (1.3 hli).Tsis tas li ntawd, kev txav mus los tau ruaj khov ntawm \(\kwv yees) ntawm 4 mus rau 4.5 hli thiab los ntawm 6 mus rau 7 hli rau asymmetric thiab axisymmetric tilts, raws li (Fig. 9a, b).Lub tswv yim tseem ceeb ntawm qhov kev tshawb pom no tau qhia nyob rau hauv kev tsim kev kam rau siab, piv txwv li, qhov qis dua ntawm kev pom zoo TL yuav txhais tau tias yuav tsum muaj qhov tseeb ntev dua.Nyob rau tib lub sijhawm, lub toj siab kev txav mus los muab kev kam rau siab dua rau kev xaiv qhov ntev ntawm lub dip ntawm ib zaus uas tsis muaj qhov cuam tshuam loj rau kev txav mus los.
Txoj kev tshawb no suav nrog cov kev txwv hauv qab no.Kev ntsuas ncaj qha ntawm rab koob deflection siv qhov ntsuas ntug thiab kev ntsuas siab ceev (Daim duab 12) txhais tau hais tias peb tsuas yog txwv rau cov xov xwm optically pob tshab xws li huab cua thiab dej.Peb kuj tseem xav taw qhia tias peb tsis tau siv cov kev sim los sim simulated hloov mus rau lwm qhov, tab sis siv cov kev tshawb fawb FEM los txiav txim siab qhov ntev ntev rau kev tsim cov koob.Hais txog cov kev txwv, qhov ntev ntawm lub lancet ntawm lub taub hau rau lub tes tsho yog \(\ kwv yees) 0.4 cm ntev dua li lwm cov koob (AX1-3), saib daim duab.3b ib.Qhov no tuaj yeem cuam tshuam cov lus teb modal ntawm rab koob tsim.Tsis tas li ntawd, cov duab thiab ntim ntawm qhov kawg ntawm tus pin waveguide (saib daim duab 3) tuaj yeem cuam tshuam rau cov neeg kho tshuab impedance ntawm tus pin tsim, qhia txog kev ua yuam kev ntawm cov neeg kho tshuab impedance thiab khoov tus cwj pwm.
Thaum kawg, peb tau pom tias qhov kev sim bevel geometry cuam tshuam tus nqi ntawm deflection hauv USeFNAB.Yog tias qhov deflection loj dua yuav muaj txiaj ntsig zoo rau cov txiaj ntsig ntawm rab koob ntawm cov ntaub so ntswg, xws li kev ua haujlwm ntawm kev txiav tom qab tho, tom qab ntawd ib lub lancet zoo tuaj yeem pom zoo hauv USeFNAB vim nws muab qhov siab tshaj plaws deflection thaum tswj kev nruj txaus ntawm cov txheej txheem..Ntxiv mus, ib txoj kev tshawb fawb tsis ntev los no 35 tau pom tias qhov kev hloov pauv ntau dua tuaj yeem txhim kho cov teebmeem lom neeg xws li cavitation, uas tuaj yeem pab txhawb kev txhim kho ntawm kev siv phais mob tsawg.Muab hais tias nce tag nrho lub zog acoustic tau pom tias yuav ua rau muaj pes tsawg tus biopsies hauv USeFNAB13, kev tshawb fawb ntxiv ntawm cov qauv kom muaj nuj nqis thiab kev ua tau zoo yog xav tau los ntsuas cov ncauj lus kom ntxaws cov txiaj ntsig ntawm kev tshawb fawb koob geometry.
Post lub sij hawm: Jan-06-2023