3D reconstruction is one of the most challenging problems in computer vision. This project uses CAD model to increase the accuracy,robustness and speed of 3D reconstruction and five different works are conducted: 1 research on space curve 3D reconstruction method based on high curvature point nad turning point; 2 free-form curve 3D reconstruction based on B-spline and BURBS; 3 Active surface affine reconstruction based on single frame; 4 Matching and reconstruction of 3D sparse points; Data fitting method based on the iteration of nearest point.

三維重建是計(jì)算機(jī)視覺(jué)中公認(rèn)的難題黄色免费强奸视频网站，本項(xiàng)目使用CAD模型來(lái)提高三維重建的精度、穩(wěn)健性和速度的思路在线播放欧美特级黄色视频，圍繞著空間曲線(xiàn)和曲面的三維重建和匹配開(kāi)展了以下五個(gè)方面的研究：1）基于高曲率點(diǎn)和拐點(diǎn)分割的空間曲線(xiàn)三維重建方法研究欧美一区日韩在线播放；2）基于B樣條和NURBS表示的空間自由曲線(xiàn)三維重建方法研究；3）基于單幀圖像的有源曲面仿射重建日本二区三区欧美亚洲国产；4）三維離散數(shù)據(jù)的匹配與重建在线免费A片；5）基于迭代最近點(diǎn)的數(shù)據(jù)擬合方法。

The raw data was processed by using axial, coronal and double oblique multi-planar reformation; Images obtained were graded in terms of quality with a 5-point scale(5=excellent, 4=good, 3=fair, 2=poor, and 1=nondiagnostic). In grading image quality at axial MPR, The radiologic specialists focused on the subarcuate fossa, tendon of tensor tympani, facial recess, vestibular aqueduct and pyramidal eminence, In grading image quality at coronal MPR, attention was given to the scute, crista transversa, fenestra cochleae, lateral malleal ligament and snake eyes signature of cranial nerve, In the grading of the image quality at double oblique MPR, the radiologic specialists concentrated on the malleus, incus, stirrup bone, upper bony semicircular and aquaeductus fallopii, and then to implement statistical analysis. In order to choose the minimum tube current values and the maximum pitch that can satisfy the diagnosis request, image quality of axial, coronal and double oblique reformation images was compared with different tube current groups. 15 ears of volunteers were used to test the validity with the scanning parameter. Subsequently noise, MTF and dose length product were measured by phantoms in different tube current and pitch, the parameters obtained were compared and taken into statistics analysis.

掃描模式使用臨床常用的顳骨螺旋掃描方式：管電壓120 kV欧美亚洲福利，準(zhǔn)直寬度20×0.6 mm草榴1024最新地址，視野200 mm，重建矩陣512×512欧美精品熟妇人妻在线视频，旋轉(zhuǎn)時(shí)間1 s/r无码一级爽视频在线播放，重建層厚0.6 mm，重建間隔0.3 mm中文字幕日本αv一区二区，分別改變管電流(380AV线天堂久、300、200在线黄色网站视频、160亚洲欧美日韩无、120和80 mA)和螺距(0.8、1.0和1.2)進(jìn)行掃描和重建一级黄色网站直接看，然后對(duì)顳骨進(jìn)行橫斷面2018年一级黄片、冠狀面和雙斜面多平面重組，于重組后的橫斷層面圖像上選取弓形下窩精品一区二区三区换着人妻玩、鼓膜張肌腱婬乱A片欧美大片、面神經(jīng)隱窩、前庭導(dǎo)水管和錐隆起5個(gè)解剖結(jié)構(gòu)www.毛片,com，冠狀面重組圖像上選取盾板噢美性爱操你啦、橫嵴、蝸窗网站黄se、面神經(jīng)的蛇眼征和錘骨外側(cè)韌帶5個(gè)解剖結(jié)構(gòu)国内精品在线观看，雙斜面重組圖像上選取錘骨人人操人人摸人人干五月、砧骨、鐙骨小说视频图片精品区、上骨半規(guī)管和面神經(jīng)管5個(gè)解剖結(jié)構(gòu)国产v亚洲v欧美v专区，在雙盲的情況下由放射學(xué)專(zhuān)家分別對(duì)各管電流和螺距下掃描的重組圖像進(jìn)行評(píng)分，隨后進(jìn)行統(tǒng)計(jì)學(xué)處理欧美专区在线，從中篩選出滿(mǎn)足診斷要求的最低管電流值和最大的螺距精彩美女一区二区v，分別采用患者25例(15耳)用該管電流值和螺距驗(yàn)證其可行性；然后利用模體分別測(cè)試各管電流和螺距下的圖像的空間分辨率一区二区精品在线、噪聲及其劑量長(zhǎng)度積日批视频在线播放，并對(duì)測(cè)試所得參數(shù)數(shù)值進(jìn)行比較和統(tǒng)計(jì)學(xué)處理。

After certifying the irreality of ideal filtering function, we can get a better filter selecting a proper window function. Comparing two actual filters, we designate a good"Panama hat"filtering function. Meanwhile, an effectively linear interpolating function is introduced to raise the image reconstruction quality. Describing its realizing steps on the micro-computer briefly, we reconstructed some images from the anlogue projections of some models. The number of projection views is 180, 100 same interval parallel lines per view; the size of reconstructed images is 64×64 pixels with 64 gray levels; the reconstructing speeds are 40" on PC-386 and 12"on PC-486, respectively; each pixel is 0.31mm.

在證明了理想濾波器的不可實(shí)現(xiàn)性之后日本免费第一网站，得知通過(guò)選擇適當(dāng)?shù)拇昂瘮?shù)可獲得很好的濾波函數(shù)超碰在线婷婷，經(jīng)過(guò)兩個(gè)實(shí)際濾波器的效果對(duì)比，我們選取了較好的"巴拿馬帽"形濾波函數(shù)国产最爽的乱婬视频a群体，同時(shí)也介紹了一個(gè)有效的提高重建質(zhì)量的線(xiàn)性?xún)?nèi)插函數(shù)男人强奷女人视频120分钟，概要地?cái)⑹隽似叫猩涫鴪D象重建的計(jì)算機(jī)具體實(shí)現(xiàn)步驟后，對(duì)幾個(gè)物體的模擬投影數(shù)據(jù)進(jìn)行了重建：投影角為180°h福利视频网站，每視角下有100個(gè)平行投影數(shù)據(jù)點(diǎn)免费一终婬片A片AAA毛片，在386微機(jī)上重建尺寸為64×64，時(shí)間約為40秒天天av天天操；在486/33MHz微機(jī)上只用了12秒免费在线观看一级黄色视频网址免费在线观看，圖象的象點(diǎn)精度是0.31mm。

An iterative factorization method based on linear subspace for projective reconstruction is presented in the paper. It relies on the facts that the rows in the matrix including all the image points span the same linear subspace as the rows in the matrix including space points and the fact that any basis of the subspace can be regarded as projective reconstruction. The projective reconstruction and the depth factors are obtained based on linear iteration.

摘要該文提出了一種基于子空間線(xiàn)性迭代的射影重建方法欧美高清不卡一区，該方法利用所有的圖像序列構(gòu)成的行向量生成的線(xiàn)性子空間之和與射影重建結(jié)構(gòu)點(diǎn)構(gòu)成的行向量生成的子空間是同一線(xiàn)性子空間及在該子空間中任何一個(gè)基底都可以作為射影重建的特性麻豆国产福利91在线，線(xiàn)性迭代地求取射影重建及圖像深度因子。

The reconstruction problem is ill-posed, so two optimal criterions, the least module and the smoothness criterion base on Tikhonov regularization technique, are introduced into reconstruction algorithm. Many regularization parameters choice strategies are investigated, and the TPA(Two—Parameter Algorithm) strategy which is based on the Morozov discrepancy principles, is implemented in two regularization reconstruction algorithms.Numerical experiment results show that the nonnegative and smoothness constraint condition can overcome the difficulty of iteration semiconvergent, preconditioned technique can improve convergence rate and reconstruction accuracy, smoothness regularization criterion can meliorate ill-posed problem of reconstruction and enhance iteration stability, and the TPA is an effective strategy of regularization parameters choice.

數(shù)值試驗(yàn)表明：在共軛梯度法中引入非負(fù)約束和光滑約束改善了迭代的"半收斂"性欧美三级黄色网址，非負(fù)約束保證了解的非負(fù)性99riav32，光滑約束抑制了重建解的振蕩現(xiàn)象，約束算法的重建精度與無(wú)約束算法相比大幅度提高在线超碰网站；在約束共軛梯度重建算法中引入預(yù)優(yōu)技術(shù)色色影院黄色视频，可以加快算法的收斂速度，提高迭代的穩(wěn)定性和重建精度黄片毛；引入光滑準(zhǔn)則的正則化技術(shù)可以有效改善圖像重建問(wèn)題的不適定性日本强伦姧人妻网站，加快迭代的收斂速度，提高迭代的穩(wěn)定性和圖像重建質(zhì)量717午夜理论电影网，計(jì)算正則參數(shù)的TPA算法在閃光照相圖像重建中是有效的手机看片,你懂的。

The advantages of this new method are:(1) The field conductivity distribution function is fitter the actual condition than tradition methods:(2) On the condition of triangle elements cut of field, making the calculation speed increase in large degree than tradition methods.

與單元電導(dǎo)率重建算法相比，節(jié)點(diǎn)電導(dǎo)率重建算法的優(yōu)點(diǎn)有：(1)使場(chǎng)域電導(dǎo)率分布函數(shù)更符合實(shí)際情況，克服了傳統(tǒng)算法中對(duì)電導(dǎo)率作離散化處理的缺陷色哟哟国产精品一区在线观看；(2)當(dāng)場(chǎng)域采用三角形單元剖分方式時(shí)国产一级毛片又粗又黄又硬，在場(chǎng)域的剖分密度保持不變的情況下，可以大大提高重建計(jì)算的速度色色网激情网；(3)在場(chǎng)域采用三角形單元剖分方式時(shí)国产第二页，場(chǎng)域的剖分密度可以比以前加大一倍，在不降低重建計(jì)算速度的前提下黄片xxxxx，可以改善重建計(jì)算的精度；(4)由于重建的是所有節(jié)點(diǎn)的電導(dǎo)率久久婷婷加勒比一本到，避免了先前單元電導(dǎo)率重建圖像中"階梯"狀邊緣和"鋸齒"狀邊緣的出現(xiàn)网站在线播放你懂的，明顯地改善了圖像的視覺(jué)效果。

It shows that the lensless Fourier transform digital hologram can be reconstructed at any distance by Fresnel transform algorithm. For convolution algorithm,the whole reconstructed image with high resolution can be acquired in an optimal reconstruction range or a small area around it.

結(jié)果表明：利用菲涅耳變換算法對(duì)離軸無(wú)透鏡傅里葉變換數(shù)字全息進(jìn)行重建時(shí)网址国产，無(wú)重建距離的限制自拍偷拍亚洲天堂；采用卷積重建法只能在最佳再現(xiàn)距離附近一個(gè)非常小的范圍內(nèi)才能獲得高分辨率再現(xiàn)像；而采用角譜重建法在略小于最佳再現(xiàn)距離及大于最佳再現(xiàn)距離較大范圍內(nèi)重建国产mv最爽乱婬视频免费看，均能獲得高分辨率的再現(xiàn)像欧洲日韩亚洲无线无码AV。

Two construction methods for fewer views from limited range—ART and SART are studied, and simulated a physical fields views whose variation of deflection is equal to double-Gauss function, and then reconstructed it, and still analyzed the accuracy of the reconstruction methods.After study and analysis on the theory of ART and SART, and after analysis the properties resulted from their theory root cause, A modified simultaneous algebraic reconstruction method is presented, which is based on ART, this method takes into account both the pixel itself and the pixels close by it which are crossed by the same ray.

論文研究了兩種有限投影方向的非軸對(duì)稱(chēng)場(chǎng)的CT重建算法——代數(shù)重建法和聯(lián)合代數(shù)重建法，并用VC++程序模擬實(shí)現(xiàn)了折射率分布為雙高斯函數(shù)的場(chǎng)的正向投影及重建過(guò)程免费一级久久黄色视频，并對(duì)所用算法的重建精度進(jìn)行了分析黄色片子网址。

The reconstruction problem is ill-posed, so two optimal criterions, the least module and the smoothness criterion base on Tikhonov regularization technique, are introduced into reconstruction algorithm. Many regularization parameters choice strategies are investigated, and the TPA(Two—Parameter Algorithm) strategy which is based on the Morozov discrepancy principles, is implemented in two regularization reconstruction algorithms.Numerical experiment results show that the nonnegative and smoothness constraint condition can overcome the difficulty of iteration semiconvergent, preconditioned technique can improve convergence rate and reconstruction accuracy, smoothness regularization criterion can meliorate ill-posed problem of reconstruction and enhance iteration stability, and the TPA is an effective strategy of regularization parameters choice.

數(shù)值試驗(yàn)表明：在共軛梯度法中引入非負(fù)約束和光滑約束改善了迭代的&半收斂&性，非負(fù)約束保證了解的非負(fù)性99r精品在线观看，光滑約束抑制了重建解的振蕩現(xiàn)象网站视频你懂的，約束算法的重建精度與無(wú)約束算法相比大幅度提高；在約束共軛梯度重建算法中引入預(yù)優(yōu)技術(shù)欧美性爱1区，可以加快算法的收斂速度人人色人人橾人人色人人橾，提高迭代的穩(wěn)定性和重建精度；引入光滑準(zhǔn)則的正則化技術(shù)可以有效改善圖像重建問(wèn)題的不適定性黄色三级网，加快迭代的收斂速度黄色视频免费区，提高迭代的穩(wěn)定性和圖像重建質(zhì)量，計(jì)算正則參數(shù)的TPA算法在閃光照相圖像重建中是有效的亚洲第五十九页。

On the basement of conventional direct fan-beam reconstruction, this paper gives a newly improved algorithm-"fast filtering-backprojection". This method utilizes the symmetrical circle geometry to sample projection data, and reconstructs image on the Polarcoordinate firstly, then translates this reconstructed image onto the cartesian coordinate system with two interpolating operations so that the computer can show the result image on the VGA screen. This algorithm rebates the calculating backprojection greatly, and shortens a few times of reconstructing time than same kinds of means. With the size of image enlarging, the reconstructing time abates with 2 exponent times. In addition, according to the idea of parallel-beam, we rearrange the fan-beams and reconstruct image using parallel-beam method fastly. The rearranging constraint condition is given here.

本文首先在傳統(tǒng)的扇束直接重建方法的基礎(chǔ)上a片一级视频，提出了一個(gè)改進(jìn)的快速濾波反投影重建算法，它利用旋轉(zhuǎn)采集投影數(shù)據(jù)的圓周對(duì)稱(chēng)的幾何關(guān)系在线A片中文亚洲，先在極坐標(biāo)系統(tǒng)內(nèi)進(jìn)行圖象的重建国内免费自拍1视频在线观看网址，然后通過(guò)兩次內(nèi)插運(yùn)算再將圖象轉(zhuǎn)換到計(jì)算機(jī)顯示方式下的笛卡爾坐標(biāo)系中去，該方法將以往的直接重建方法中的反投影時(shí)所需的運(yùn)算大大降低亚洲区国产日韩区在线观看，并將重建時(shí)間比同類(lèi)方法縮短了幾倍东北女人叫床大片毛片AA，而且隨著重建圖象的尺寸的增大，重建時(shí)間以2的指數(shù)次方倍相對(duì)縮短国产城中村嫖妓播放观看，并獲得了較好質(zhì)量的重建圖象性交网址在线观看；另外www.Heyoz.com，又根據(jù)平行束投影重建圖象的思想，對(duì)扇形射束進(jìn)行了重排一级a片XX，然后利用平行束重建圖象的方法進(jìn)行扇束的重建A片一级二级三级，并推導(dǎo)了&扇束重排重建圖象&方法的約束條件。