17519745
Surface Reconstruction From Non-parallel Curve Networks
Building surfaces from cross-section curves has wide applications including bio-medical modeling. Previous work in this area has mostly focused on connecting simple closed curves on parallel cross-sections. Here we consider the more general problem where input data may lie on non-parallel cross-sections and consist of curve networks that represent the segmentation of the underlying object by different material or tissue types (e.g., skin, muscle, bone, etc.) on each cross-section. The desired output is a surface network that models both the exterior surface and the internal partitioning of the object. We introduce an algorithm that is capable of handling curve networks of arbitrary shape and topology on cross-section planes with arbitrary orientations. Our algorithm is simple to implement and is guaranteed to produce a closed surface network that interpolates the curve network on each cross-section. Our method is demonstrated on both synthetic and bio-medical examples.
13366067
Tarsal and Metatarsal Bone Mineral Density Measurement Using Volumetric Quantitative Computed Tomography
A new method for measuring bone mineral density (BMD) of the tarsal and metatarsals is described using volumetric quantitative computed tomography (VQCT) in subjects with diabetes mellitus and peripheral neuropathy. VQCT images of a single foot were acquired twice from eight subjects (mean age 51 [11 SD], seven males, one female). The cortical shells of the seven tarsal and five metatarsal bones were identified and semiautomatically segmented from adjacent bones. Volume and BMD of each bone were measured separately from the two acquired scans for each subject. Whole-bone semiautomatic segmentation measurement errors were determined as the root mean square coefficient of variation for the volume and BMD of 0.8% and 0.9%, respectively. In addition to the whole-bone segmentation methods, we performed atlas-based partitioning of subregions within the second metatarsal for all subjects, from which the volumes and BMDs were obtained for each subregion. The subregion measurement BMD errors (root mean square coefficient of variation) within the shaft, proximal end, and distal end were shown to vary by approximately 1% between the two scans of each subject. The new methods demonstrated large variations in BMDs between the 12 bones of the foot within a subject and between subjects, and between subregions within the second metatarsal. These methods can provide an important outcome measure for clinical research trials investigating the effects of interventions, aging, or disease progression on bone loss, or gain, in individual foot bones.
42568731
Defining and computing multi-dimensional skeletons
Describing shapes is an important task in graphics and vision. A simple, concise descriptor that captures the essential shape properties of an object would greatly facilitate computer-based understanding of the object and applications such as matching and segmentation. For this reason, medial axes (MA) has become a popular shape descriptor since its introduction by Blum [Blum 1967]. The MA of an N-D object is an (N -- 1)-D geometry centered within the object. For example, the MA of a 2D object consists of medial curves at elongated parts, whereas the MA of a 3D object consists of medial surfaces describing the protrusions on the object.
27964880
Surface reconstruction from point set using projection operator
Step 1: Lay a grid over the input point set. Step 3: Mark all grid edges with projection vectors at their two ends pointing in opposite directions. Approximate the intersection points between the surface and these edges based on the magnitudes of their projection vectors. Step 4: For each grid cell, calculate a grid center as the average of all intersection points. For each marked edge, connect the centers of its incident cells to make a piece of the surface.
1115065
An interactive tool for fitting surfaces to volume data
MRI and CT scanners have long been used to produce threeWe begin with a volume dataset. In this example, we have a CT scan of a human prostate. There are 256 slices. The figure to the right shows one input slice, along with rectangles that outline the locations of every 10th slice. We perform linear interpolation between each slice in the input dataset, and now we can render arbitrarily oriented image planes. The figure to the right shows one such plane.
17430531
Interactive Separation of Segmented Bones in CT Volumes Using Graph Cut
We present a fast, interactive method for separating bones that have been collectively segmented from a CT volume. Given user-provided seed points, the method computes the separation as a multi-way cut on a weighted graph constructed from the binary, segmented volume. By properly designing and weighting the graph, we show that the resulting cut can accurately be placed at bone-interfaces using only a small number of seed points even when the data is noisy. The method has been implemented with an interactive graphical interface, and used to separate the 12 human foot bones in 10 CT volumes. The interactive tool produced compatible result with a ground-truth separation, generated by a completely manual labelling procedure, while reducing the human interaction time from a mean of 2.4 hours per volume in manual labelling down to approximately 18 minutes.
15609476
An Online Personalized Recommendation Model Based on Bayesian Networks
It is one of an important method of using Bayesian networks in electronic commercial recommended system. But the models of Bayesian networks for describing recommended system have a problem that it could not learn online. The paper puts forward an online personalized recommended model based on Bayesian networks. The paper uses a partial ordering to represent previous structure and find posterior distributions of every node on the orders to realize online structure learning. It also uses a correctional function to revise log likelihood for online parameter learning. The experiment shows that the model can be learned online for personalized recommended system.
17479734
Self-Organization of Autonomous Peers with Human Strategies
Similarly to social networks where people are connected by their social relationships, two autonomous peer nodes can be connected in unstructured peer-to-peer (P2P) networks if users in those nodes are interested in each other's data. The similarity between P2P networks and social networks, where peer nodes are people and connections are relationships, leads us to believe that human strategies in social networks are useful for improving the performance of resource discovery by self-organising autonomous peers on unstructured P2P networks. In this paper, we present an efficient social-like peer-to-peer (ESLP) model for resource discovery by mimicking different human behaviours in social networks.
46086944
A Research on Dissipative Structure of the Information Resource Organization of E-Government
Government information resource is the foundation of e-government, and government information resource organization pattern is the key factor that affects sustainable development of e-government. At present, a lack of the systematic plan in government information resource organization exists universally. The primary reason is that systematization and formalization of research on government information resource organization pattern is insufficient and lacks support to organize and plan the government information resource. This article starts with the basic assumption of the government information hyper-cycle system consisting of e-government and its object system, depicts the dissipative structure of government information resource organization through introducing superior-rank operator and lower-rank operator in algebra system, and explores actively the self-organized, extensible and universal government information resource organization pattern based on hyper-cycle (PBHC) systematic plan.
3090205
Challenges for End-to-End Quality of Service in Heterogeneous Networks
To guarantee the end-to-end QoS (E2E Quality of Service) in heterogeneous network is an important issue to provide pervasive and trusted service. Currently, the different networks are optimized for different services, but it becomes urgent to provide pervasive service across different networks. This paper gives an overview on how to design a dynamic and integrated QoS architecture under heterogeneous networks. This paper firstly analyzes the actuality of the E2E quality of service in heterogeneous networks, and then discusses the requirements of the E2E QoS of two types of heterogeneous networks, finally points out the five key issues to solve the practical problem in the current network.
14319592
The Development and Status of Automobile E-Commerce in China
Although the hype surrounding the promise of electronic commerce seems all pervasive currently, there is an absence of research on automobile eCommerce, especially in developing countries, which covers wide-ranging issues beyond contextual imperatives. This paper tries to fill in the gap, by analyzing the impacts of eCommerce on automobile industry in China, and the factors of eCommerce adoption and development of automobile industry in China from internal, external and contextual perspectives, after describing the internet and ecommerce in china. From the situation of automobile ecommerce in China, the paper finds that the automobile industry in China, especially automobile sales, remains only superficially affected by the ecommerce. This is a big difference from the developed countries such as U.S. The paper also displays the important aspects to the development of automobile ecommerce in China such as infrastructure, role of the central government, serving the customer better, security, customer trust, delivery, and so on.