投影地

Key words: windows function; image reconstruction; convention back projection; fan beam scan model

通过实验，验证了基于窗函数的卷积反投影图像重建算法可以有效地提高重建图像的质量。

In order to effectively abstract the texture and denoise but not damage the edge and other important details of image, Meyer (2001) proposed using elements of BV space and G space to characterize cartoon and details of image respectively. The authors present PDE of minimizing energy on the basis of Meyer's work, After the model is discretizated. projection algorithm and the method for ROF model are applied. Thus an image is decomposed into two parts, bounded variation component u and texture with noise υ.

为有效地提取纹理和去噪而不损坏图像的边缘及其他重要细节，Meyer(2001)提出了分别用BV空间和G空间刻画图像的主体和细节部分，笔者在Meyer的图像分解模型基础上，建立能量最小化PDE方程，将模型离散化后，利用投影算法和ROF模型的求解方法，将图像分解为有界变差部分u和包含纹理和噪声的部分υ。

Its universality: its democratic equality and constancy to its nature in seeking its own level: its vastness in the ocean of Mercator's projection: its unplumbed profundity in the Sundam trench of the Pacific exceeding 8000 fathoms: the restlessness of its waves and surface particles visiting in turn all points of its seaboard: the independence of its units: the variability of states of sea: its hydrostatic quiescence in calm: its hydrokinetic turgidity in neap and spring tides: its subsidence after devastation: its sterility in the circumpolar icecaps, arctic and antarctic: its climatic and commercial significance: its preponderance of 3 to 1 over the dry land of the globe: its indisputable hegemony extending in square leagues over all the region below the subequatorial tropic of Capricorn: the multisecular stability of its primeval basin: its luteofulvous bed: its capacity to dissolve and hold in solution all soluble substances including millions of tons of the most precious metals: its slow erosions of peninsulas and islands, its persistent formation of homothetic islands, peninsulas and downwardtending promontories: its alluvial deposits: its weight and volume and density: its imperturbability in lagoons and highland tarns: its gradation of colours in the torrid and temperate and frigid zones: its vehicular ramifications in continental lakecontained streams and confluent oceanflowing rivers with their tributaries and transoceanic currents, gulfstream, north and south equatorial courses: its violence in seaquakes, waterspouts, Artesian wells, eruptions, torrents, eddies, freshets, spates, groundswells, watersheds, waterpartings, geysers, cataracts, whirlpools, maelstroms, inundations, deluges, cloudbursts: its vast circumterrestrial ahorizontal curve: its secrecy in springs and latent humidity, revealed by rhabdomantic or hygrometric instruments and exemplified by the well by the hole in the wall at Ashtown gate, saturation of air, distillation of dew: the simplicity of its composition, two constituent parts of hydrogen with one constituent part of oxygen: its healing virtues: its buoyancy in the waters of the Dead Sea: its persevering penetrativeness in runnels, gullies, inadequate dams, leaks on shipboard: its properties for cleansing, quenching thirst and fire, nourishing vegetation: its infallibility as paradigm and paragon: its metamorphoses as vapour, mist, cloud, rain, sleet, snow, hail: its strength in rigid hydrants: its variety of forms in loughs and bays and gulfs and bights and guts and lagoons and atolls and archipelagos and sounds and fjords and minches and tidal estuaries and arms of sea: its solidity in glaciers, icebergs, icefloes: its docility in working hydraulic millwheels, turbines, dynamos, electric power stations, bleachworks, tanneries, scutchmills: its utility in canals, rivers, if navigable, floating and graving docks: its potentiality derivable from harnessed tides or watercourses falling from level to level: its submarine fauna and flora, numerically, if not literally, the inhabitants of the globe: its ubiquity as constituting 90 percent of the human body: the noxiousness of its effluvia in lacustrine marshes, pestilential fens, faded flowerwater, stagnant pools in the waning moon.

50它的普遍性，它的民主的平等性，以及保持着它自身求平的本质。用墨卡托投影法在地图上所标示出的浩淼的海洋；太平洋中巽他海沟那超过八千噚的不可测的深度；永不消停、后浪推前浪地冲刷着海岸线每一部位的波涛以及水面上的微粒子；水的单位粒子的独立性；海洋变幻莫测；根据液体静力学，风平浪静时它纹丝不动；根据液体动力学，小潮大潮时它便涨了起来。暴风雨后一片沉寂；北极圈与南极圈冰冠地带的不毛性以及对气候及贸易的影响；跟地球上的陆地相比占三对一优势；它在亚赤道带南回归线以南的整个区域延伸无数平方海里的绝对权威；其在原始海盆里数千万年以来所保持的稳定性；它那橙红色海床；它那把包括数百万吨贵金属在内的可溶解物质加以溶解，并使之保持在溶解状态的性能；它对半岛和有下陷趋势的岬角所产生的缓慢的浸蚀作用；其冲积层；其重量、容积与浓度；它在咸水湖、高山湖里的静谧；其色调因热带、温带和寒带而变为或浓或淡；与陆上的湖泊、溪流及支流汇合后注入海洋的河川，还有横跨大洋的潮流所构成的运输网。沿着赤道下面的水路自北向南的湾流；海震、水龙卷、自流井、喷泉、湍流、漩涡、河水暴涨、倾盆大雨、海啸、流域、分水岭、间歇泉、大瀑布、漩流、海漩、洪水、泛滥、暴雨等滥施淫威；环绕陆地的上层土壤那漫长的曲线；源泉的奥秘可用探矿杖来占卜或用湿度测定器来揭示；阿什汤大门的墙壁上的洞、空气的饱和与露水的蒸发能够证明那潜在的湿度；水的成分单纯，是氢二、氧一的化合物；水的疗效；水的死海里的浮力；它在小溪、涧谷、水坝的缝隙、船舷的裂口所显示的顽强的浸透性；它那清除污垢、解渴、灭火、滋养植物的性能；作为模范和典型，它的可靠性；它变化多端：雾、霭、云、雨、麦、雪、雹；并在坚固的消防龙头上发挥出压力；而且千姿百态：湖泊、湖岔、内海、海湾、海岬、环礁湖、环状珊瑚岛、多岛海、海峡、峡江、明奇、潮汐港湾、港湾；冰河、冰山、浮动冰原显示出它是何等坚硬；在运转水车、水轮机、发电机、发电厂、漂白作坊、鞣皮厂、打麻厂时，它又是那样驯顺；它在运河、可航行的河川、浮船坞和干船坞所起的作用；潮汐的动力化或利用水路的落差使它得以发挥潜力；海底那些成群的动物和植物虽然并非名副其实地栖息在地球上，论数目却占地球上生物的一大半；水无所不在，占人体的百分之九十；在沼泽地、闹瘟疫的湿地、馊了的花露水以及月亏期那淤积污浊的水塘子，水所散发的恶臭充满了毒气。

Mental world is always unpredictable, the outer world project individual situation are always floweriness,"Exposure" as this display's subject, itself implies an mode of uneasiness, borrow this vocabulary more absorbed positive elements of acceptation and through display the art works to clear up this insecurity by artists, and to provide the spectators countless possibility of suspect.

心理的世界总是变幻莫测的，外部世界投影在个人内心的悸动也是绚烂多姿的，此次画展题为"曝光"，曝光本身暗含着一种不自在的心理状态，而展览中借用曝光一词则更多地吸纳了词义中积极的成份，是由艺术家通过作品的展示来对这种不安全因素地消解，也给观者提供了无数猜想的可能性

In this approach, a homography matrix between the ground plane and the image plane is obtained by least square.

它首先利用地平面与图像中的对应点建立一个对应矩阵（homogra-phy），然后利用已知的摄像机高度以及地面上垂线在图像中的投影等约束信息来求取摄像机的参数。

At first, the area of the mouth is segmented by using the value vertical and horizontal projection of red pixel.

首先，采用红色像素点进行水平和垂直投影的方法对嘴唇进行区域分割，然后再利用边缘提取和红色像素点提取相结合的方法对嘴唇进行提取，此方法可以有效地去除嘴唇周围的阴影干扰和其它干扰，完整地将嘴唇从原图中分割提取出来。

Different from the traditional approach of solving GDA by singular value decomposition,the new algorithm utilizes kernel modified Gram-Schmidt orthogonalization algorithm to extract the optimal transformation matrix directly,which can not only effectively hold the most discriminant information in the null space of within-class scatter matrix,but also make the solution more stable in numeric.

与传统用奇异值分解获取目标特征子空间的方式不同，新算法运用核修正格兰-施密特正交化过程直接提取最优投影变换矩阵，不仅有效地地保留了类内散度矩阵最具辨别力的零空间信息，同时使所求解在数值上更稳定。

The scientific choice of city public transit line is beneficial to traffic conduction.

在城市中科学地选择公交线路对输导交通有着很重要的意义，作为公交线路模型在无线传感器网路模型中的投影，科学地建立骨干网也是具有重要意义的。

Topography map of the hip bone displays the depth of all parts of the hip bone and the projection of important blood vessel and nerve onto the hip bone imaginarily and directly. Deep understanding of topography map of the hip bone may prevent vital blood vessel and nerve from accidental injury during the operation of internal fixation of pelvic fracture and acetabular fracture.

提示髋骨的地形图形象、直观地表达了髋骨各个部位的厚度、重要血管和神经在髋骨表面的投影，深入地了解髋骨的地形图能够在骨盆骨折和髋臼骨折内固定中防止重要血管和神经的意外损伤发生。

Topographic map of the pelvis expresses the depth of all parts of the pelvis, the projection of important blood vessels and nerves in the pelvis imaginarily and directly. To understand deeply the topography map of the pelvis may prevent vital blood vessel and nerve from accidental injury during the operation of internal fixation of pelvic fracture and acetabular fracture.

骨盆地形图形象、直观地表达了骨盆各个部位的厚度、重要血管和神经在骨盆表面的投影，深人地理解骨盆地形图能够在骨盆骨折和髓臼骨折内固定手术中防止发生重要血管和神经的意外损伤。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。