Treatment of cranium and maxilla defects using CAD/ CA M techniques has been under the way. This makes it possible to rehabilitate the defective skull, to protect the intracranial structure from damage and to give t h...Treatment of cranium and maxilla defects using CAD/ CA M techniques has been under the way. This makes it possible to rehabilitate the defective skull, to protect the intracranial structure from damage and to give t he patient an individual implant with satisfying visual effect at same time. The general process of treatment are picking-up the shape information of defective skull from CT pictures of the patient, reconstructing 3-dimensional model of t he defect part, transforming the image data into manufacture data, and manufactu ring stage by means of choosing manufacture methods and certain material. As the prophase work a set of techniques was illustrated in the paper. The way of transforming helical CT data into an individual implant was introduced generally . Meanwhile, a prospective study of computer aided design and manufacture of tit anium skull for cranioplasty was reported. On these basic efforts, several resea rches and developments of relative techniques were described in detail inclu ding data conversion, 3-dimensional modeling and acquisition of the defect part geometric model. Data conversion focused on three points. The first one is about transforming the original CT information into digital data. The second one is about converting t he bitmap format data into vectorgraph format that is available for geometric mo deling in CAD system. And the third one is about finding a datum of all sect ion information in order to put the single slices together. The reconstructing o f 3-demetional entire skull model is achieved with two kinds of model. The 3D w ire model, which consists of a set of wires, is accomplished by translating the 2D plane information into 3D data in CAD system. This wire model is constructed ulteriorly to a surface model. During the efforts of gaining the surfaces geomet ry of the defect part, different means is used depending on where the defect loc ation is. Once the numerical based 3-dimensional model of the skull defect is e stablished the fixation design becomes a critical factors during the surgery, wh ich decides the vision effect and plays an important role in the success of the operation. For a finer prognosis a fixation interface, which is generated by the borders of the defect part and the surface contours considering the non-affect ed neighboring contours, is arranged.展开更多
根据现有尺寸标注软件的不足,提出了尺寸标注实体的概念,因而为系统地解决尺寸标注问题打下了基础.在建立数据结构时,第一次提出了简单尺寸标注和复杂尺寸标注的概念,合理地解决了各类尺寸标注的管理问题.文中还对机械图中的尺寸标注进...根据现有尺寸标注软件的不足,提出了尺寸标注实体的概念,因而为系统地解决尺寸标注问题打下了基础.在建立数据结构时,第一次提出了简单尺寸标注和复杂尺寸标注的概念,合理地解决了各类尺寸标注的管理问题.文中还对机械图中的尺寸标注进行了规格化处理.最后介绍了 DIM 的联想规则.展开更多
The paper“Fixed-point quantum continuous search algorithm with optimal query complexity”[1]presents another interesting application of quantum search algorithms by addressing one of the long-standing challenges in q...The paper“Fixed-point quantum continuous search algorithm with optimal query complexity”[1]presents another interesting application of quantum search algorithms by addressing one of the long-standing challenges in quantum computing:how to efficiently perform search over continuous domains.While Grover’s algorithm has been a cornerstone in discrete quantum search with its well-known quadratic speedup[2],many real-world problems—ranging from high-dimensional optimization to spectral analysis of infinite dimensional operators—require searching over continuous,uncountably infinite solution spaces.展开更多
文摘Treatment of cranium and maxilla defects using CAD/ CA M techniques has been under the way. This makes it possible to rehabilitate the defective skull, to protect the intracranial structure from damage and to give t he patient an individual implant with satisfying visual effect at same time. The general process of treatment are picking-up the shape information of defective skull from CT pictures of the patient, reconstructing 3-dimensional model of t he defect part, transforming the image data into manufacture data, and manufactu ring stage by means of choosing manufacture methods and certain material. As the prophase work a set of techniques was illustrated in the paper. The way of transforming helical CT data into an individual implant was introduced generally . Meanwhile, a prospective study of computer aided design and manufacture of tit anium skull for cranioplasty was reported. On these basic efforts, several resea rches and developments of relative techniques were described in detail inclu ding data conversion, 3-dimensional modeling and acquisition of the defect part geometric model. Data conversion focused on three points. The first one is about transforming the original CT information into digital data. The second one is about converting t he bitmap format data into vectorgraph format that is available for geometric mo deling in CAD system. And the third one is about finding a datum of all sect ion information in order to put the single slices together. The reconstructing o f 3-demetional entire skull model is achieved with two kinds of model. The 3D w ire model, which consists of a set of wires, is accomplished by translating the 2D plane information into 3D data in CAD system. This wire model is constructed ulteriorly to a surface model. During the efforts of gaining the surfaces geomet ry of the defect part, different means is used depending on where the defect loc ation is. Once the numerical based 3-dimensional model of the skull defect is e stablished the fixation design becomes a critical factors during the surgery, wh ich decides the vision effect and plays an important role in the success of the operation. For a finer prognosis a fixation interface, which is generated by the borders of the defect part and the surface contours considering the non-affect ed neighboring contours, is arranged.
文摘The paper“Fixed-point quantum continuous search algorithm with optimal query complexity”[1]presents another interesting application of quantum search algorithms by addressing one of the long-standing challenges in quantum computing:how to efficiently perform search over continuous domains.While Grover’s algorithm has been a cornerstone in discrete quantum search with its well-known quadratic speedup[2],many real-world problems—ranging from high-dimensional optimization to spectral analysis of infinite dimensional operators—require searching over continuous,uncountably infinite solution spaces.
