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71.
Surgery to reshape the nose with an implant has been a regular procedure for enhancing a patient’s appearance and self-confidence.
The purpose of this study was to establish a computed tomography (CT) based three-dimensional assistant plastic surgery systems,
which can provide the patients with realistic prediction of their own postoperative appearance in computer and specifically
produce a nose implant for an individual patient. Preoperative CT data and 3D reconstruction techniques were employed to generate
3D model of the patient’s skull. 3D collision detection and finite elements model deformation were then applied to simulate
nose augmentation surgery and predict postoperative appearance. According to the patient’s expectation, digital models of
the nose implants were constantly modified. When the patient is satisfied with the simulated results, custom made silicone
implants were produced by a computer controlled device. Accurately regeneration of 3D images and realistic operative simulations
could be achieved with this system. The implants produced exactly conformed to the results of simulation. No curving and reshaping
were needed during operating. The clinical results extremely matched with the simulations. The system enhances surgeon patient
communication and facilitates preoperative planning. It is especially desirable for implant surgery with less guesswork of
size, contour, and orientation of the implant. The best chance of optimal results could be achieved. 相似文献
72.
Segmenting center of interests (COIs) from pictures is an important but highly challenging problem for researchers in computer vision and image processing. The capability of understanding the meanings of pictures by computers can lead to breakthroughs in a wide range of applications including Web image search and online picture-sharing communities. In this paper, a two-level strategy is presented, which consists of a rough segmentation stage and a fine segmentation stage. In the first level, a picture is partitioned into four regions by using a block clustering method based on color and texture features, and the COI within the picture is distinguished from the background according to the principles of photographic composition. This stage aims to determine the approximate region of the target. In the second level, a novel active contour model is established based on shape information and vector method, where the image energy is defined by a hue gradient and the external energy is generated from either a triangular inner force or a supplementary force. This stage tries to extract the boundary of the target accurately. Experimental results on photos downloaded from the Internet show the feasibility and effectiveness of the proposed method. 相似文献
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Voting systems are common tools in a variety of areas. This paper studies parameterized computational complexity of control of Plurality, Condorcet and Approval voting systems, respectively. The types of controls considered include adding or deleting candidates or voters, under constructive or destructive setting. We obtain the following results: (1) constructive control by adding candidates in Plurality voting is W[2]-hard with respect to the parameter “number of added candidates”, (2) destructive control by adding candidates in Plurality voting is W[2]-hard with respect to the parameter “number of added candidates”, (3) constructive control by adding voters in Condorcet voting is W[1]-hard with respect to the parameter “number of added voters”, (4) constructive control by deleting voters in Condorcet voting is W[1]-hard with respect to the parameter “number of deleted voters”, (5) constructive control by adding voters in Approval voting is W[1]-hard with respect to the parameter “number of added voters”, and (6) constructive control by deleting voters in Approval voting is W[2]-hard with respect to the parameter “number of deleted voters”. 相似文献
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Multimedia Tools and Applications - Recently, with the widespread popularity of SNS (Social Network Service), such as Twitter, Facebook, people are increasingly accustomed to sharing feeling,... 相似文献
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Multimedia Tools and Applications - Video quality assessment is an important issue for Internet Content Providers (ICPs) to improve their service. Some research has been done on objective video... 相似文献