20747570
An Energy-efficient Disjoint Path Routing Approach for Wireless Ad-hoc Networks
Apparatus and method are provided for assessing the direction of fixation of an eye by detecting polarization-related changes in light retroreflected from the fundus of the eye. Nerve fibers in the retina of the eye are birefringent and alter the polarization state of light traversing them as a function of their orientation. The nerve fibers are arrayed in a characteristic pattern in the retina, specifically radiating outward from the fovea and converging to the optic nerve head. By assessment of polarization-related changes in rctroreflected light from multiple retinal areas either sequentially or simultaneously, characteristic birefringence signatures of portions of the retina can be identified which are used to assess the direction of fixation of the eye. In addition, interference from the corneal birefringence is reduced by using incident light having a polarization state that is substantially independent of meridional direction. Circularly polarized light or non-polarized light is used for the assessment. Interference from the corneal birefringence is reduced still further by detecting polarization-related changes that are substantially independent of the meridional direction of the corneal birefringence. This is accomplished by detecting changes in ellipticity by measuring solely the Stokes parameter S3 or by measuring any two Stokes parameters. An alternative is measuring the overall intensity of the retroreflected light when the dichroism of the lutein pigment particles in the vicinity of the fovea is used for the assessment.
35951417
Tree-based Burst Aggregation in Optical Burst Switching Networks
The invention is a surface light source device capable of effectively producing polarized illumination light. The output angle of a representative beam C3 representing P-polarized component of output light from an emission surface 5 of the light guide plate 1 is about 75 DEG . Where P-polarization component of representative beam C3 is 100 (reference value), and the S-polarized component is 42.2. Representative beam C3 enters from an air layer AR to a flat surface 24g of a prism sheet 24, and then goes into the inside of prism sheet 24. At this stage the P-polarization component is 89.3 whereas the S-polarization component is 25.5. Beam C3 is incident on a slant surface 24d from its inside at an angle proximating the normal, and propagates into air layer AR between prism sheets 24, 34. Beam C3 impinges on a flat surface 34g of a prism sheet 34 while its corresponding part passes through the inside of prism sheet 34. At this stage its P-polarization component is 83.9 and its S-polarization component is 22.3. Beam C3 enters from the inside of one slope 34d of the prism array at the angle of incidence of 31 DEG . Its greater part is output to external air layer AR as illumination light substantially in the front direction.
19020033
Estimation of multiple directional light sources for synthesis of augmented reality images
We present a new method for the detection and estimation of multiple directional illuminants, using a single image of any object with known geometry and Lambertian reflectance. We use the resulting highly accurate estimates to modify virtually the illumination and geometry of a real scene and produce correctly illuminated mixed reality images. Our method obviates the need to modify the imaged scene by inserting calibration objects of any particular geometry, relying instead on partial knowledge of the geometry of the scene. Thus, the recovered multiple illuminants can be used both for image-based rendering and for shape reconstruction. Our method combines information both from the shading of the object and from shadows cast on the scene by the object. Initially we use a method based on shadows and a method based on shading independently. The shadow based method utilizes brightness variation inside the shadows cast by the object, whereas the shading based method utilizes brightness variation on the directly illuminated portions of the object. We demonstrate how the two sources of information complement each other in a number of occasions. We then describe an approach that integrates the two methods, with results superior to those obtained if the two methods are used separately. The resulting illumination information can be used (i) to render synthetic objects in a real photograph with correct illumination effects, and (ii) to virtually re-light the scene.
6236190
Estimation of multiple directional light sources for synthesis of mixed reality images
We present a new method for the detection and estimation of multiple directional illuminants, using a single image of any object with known geometry and Lambertian reflectance. We use the resulting highly accurate estimates to modify virtually the illumination and geometry of a real scene and produce correctly illuminated mixed reality images. Our method obviates the need to modify the imaged scene by inserting calibration objects of any particular geometry, relying instead on partial knowledge of the geometry of the scene. Thus, the recovered multiple illuminants can be used both for image-based rendering and for shape reconstruction. Our method combines information both from the shading of the object and from shadows cast on the scene by the object. Initially we use a method based on shadows and a method based on shading independently. The shadow based method utilizes brightness variation inside the shadows cast by the object, whereas the shading based method utilizes brightness variation on the directly illuminated portions of the object. We demonstrate how the two sources of information complement each other in a number of occasions. We then describe an approach that integrates the two methods, with results superior to those obtained if the two methods are used separately. The resulting illumination information can be used (i) to render synthetic objects in a real photograph with correct illumination effects, and (ii) to virtually re-light the scene.
9220767
Upright cluster services
The UpRight library seeks to make Byzantine fault tolerance (BFT) a simple and viable alternative to crash fault tolerance for a range of cluster services. We demonstrate UpRight by producing BFT versions of the Zookeeper lock service and the Hadoop Distributed File System (HDFS). Our design choices in UpRight favor simplifying adoption by existing applications; performance is a secondary concern. Despite these priorities, our BFT Zookeeper and BFT HDFS implementations have performance comparable with the originals while providing additional robustness.
6225988
A global optimal algorithm for class-dependent discretization of continuous data
This paper presents a new method to convert continuous variables into discrete variables for inductive machine learning. The method can be applied to pattern classification problems in machine learning and data mining. The discretization process is formulated as an optimization problem. We first use the normalized mutual information that measures the interdependence between the class labels and the variable to be discretized as the objective function, and then use fractional programming (iterative dynamic programming) to find its optimum. Unlike the majority of class-dependent discretization methods in the literature which only find the local optimum of the objective functions, the proposed method, OCDD, or Optimal Class-Dependent Discretization, finds the global optimum. The experimental results demonstrate that this algorithm is very effective in classification when coupled with popular learning systems such as C4.5 decision trees and Naive-Bayes classifier. It can be used to discretize continuous variables for many existing inductive learning systems.
18554673
Network processing performability evaluation on heterogeneous reliability multicore processors using SRN model
Future network systems and embedded infrastructure devices in ubiquitous environments will need to consume low power and process large amounts of network packet traffic. In order to meet necessary high processing efficiency requirements, future processors will have many heterogeneous cores with reduced reliability due to low voltage, small transistor sizes, semiconductor wearout, and environmental factors such as noise and interference. It will be necessary for multi-core network infrastructure software to mitigate transient hardware faults to maintain acceptable system reliability. Applications such as packet processing can benefit from the reliability versus performance tradeoff. We propose a model based on Stochastic Reward Nets to evaluate the performance vs. reliability tradeoff of unreliable embedded multi-core network processors, and apply this model to a multi-core packet processing application.