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61.
A. Pollatsek, E. D. Reichle, and K. Rayner (see record 2006-22004-014) argue that the critical findings in A. W. Inhoff, B. M. Eiter, and R. Radach (see record 2005-13471-012) are in general agreement with core assumptions of sequential attention shift models if additional assumptions and facts are considered. The current authors critically discuss the hypothesized time line of processing and indicate that the success of Pollatsek et al.'s simulation is predicated on a gross underestimation of the pretarget word's viewing duration in Inhoff et al. and that the actual data are difficult to reconcile with the strictly serial attention shift assumption. The authors also discuss attention shifting and saccade programming assumptions in the E-Z Reader model and conclude that these are not in harmony with research in related domains of study. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
A funnel, which is notable for its fundamental role in visibility algorithms, is defined as a polygon that has exactly three convex vertices, two of which are connected by a boundary edge. In this paper we investigate the visibility graph of a funnel which we call an F-graph.We first present two characterizations of an F-graph, one of whose sufficiency proof itself is a linear time Real RAM algorithm for drawing a funnel on the plane that corresponds to an F-graph. We next give a linear-time algorithm for recognizing an F-graph. When the algorithm recognizes an F-graph, it also reports one of the Hamiltonian cycles defining the boundary of its corresponding funnel. This recognition algorithm takes linear time even on a RAM.We finally show that an F-graph is weakly triangulated and therefore perfect, which agrees with the fact that perfect graphs are related to geometric structures.This work was supported in part by the Korea Science and Engineering Foundation under Grant 91-01-01. 相似文献
63.
王永纯 《哈尔滨建筑大学学报》1988,(1)
本文从设计观念和居住观念上指出两种人的心理障碍,并试图说明只要从观念上进行更新,即使是较低的建筑层高,不但是可以接受的,而且完全有可能成为一个亲切的尺度。 相似文献
64.
Emo Welzl 《Information Processing Letters》1985,20(4):167-171
Given a set S of line segments in the plane, its visibility graph GS is the undirected graph which has the endpoints of the line segments in S as nodes and in which two nodes (points) are adjacent whenever they ‘see’ each other (the line segments in S are regarded as nontransparent obstacles). It is shown that GS can be constructed in O(n2) time and space for a set S of n nonintersecting line segments. As an immediate implication, the shortest path between two points in the plane avoiding a set of n nonintersecting line segments can be computed in O(n2) time and space 相似文献
65.
5 studies were performed in order to derive a paint coloration scheme which will allow maximum aircraft visibility and detectability. It was found that maximum visibility may be expected from a large, squarelike, unbroken fluorescent red-orange area and a secondary area possessing color and brightness contrast with the fluorescent red-orange. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
Each of 12 groups of 6 Ss viewed under tachistoscopic exposure numerals in one of 12 possible combinations of 4 height-width proportions and 3 stroke widths. "1. Height-width proportion was a source of variation in visibility significant beyond the 1% level for five numerals, and beyond the 5% level for a sixth. 2. Stroke width was a significant source of variation for only one numeral. 3. The most visible combination… for all numerals is a height-width ratio of 10:7.5 and a stroke width to height ratio of 1:10." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
Kong-man ?CheungEmail author Simon?Baker Takeo?Kanade 《International Journal of Computer Vision》2005,62(3):221-247
Shape-From-Silhouette (SFS) is a shape reconstruction method which constructs a 3D shape estimate of an object using silhouette images of the object. The output of a SFS algorithm is known as the Visual Hull (VH). Traditionally SFS is either performed on static objects, or separately at each time instant in the case of videos of moving objects. In this paper we develop a theory of performing SFS across time: estimating the shape of a dynamic object (with unknown motion) by combining all of the silhouette images of the object over time. We first introduce a one dimensional element called a Bounding Edge to represent the Visual Hull. We then show that aligning two Visual Hulls using just their silhouettes is in general ambiguous and derive the geometric constraints (in terms of Bounding Edges) that govern the alignment. To break the alignment ambiguity, we combine stereo information with silhouette information and derive a Temporal SFS algorithm which consists of two steps: (1) estimate the motion of the objects over time (Visual Hull Alignment) and (2) combine the silhouette information using the estimated motion (Visual Hull Refinement). The algorithm is first developed for rigid objects and then extended to articulated objects. In the Part II of this paper we apply our temporal SFS algorithm to two human-related applications: (1) the acquisition of detailed human kinematic models and (2) marker-less motion tracking. 相似文献
68.
69.
Visibility determination is an i mportant task incomputer graphics.The goal of visibility determina-tion is to efficiently determine visible parts of themodel given a viewpoint and a viewing direction.Toachieve the output-sensitivity of the visibility algo-rithm,we exploit the idea of hierarchical adaptivebounding setting(HABS);it is used to effectivelydetermine a subset of potentially visible sets(PVS)objects.In addition,some flexible culling strategiestoi mprove frame rate per second are … 相似文献
70.
低能见度下紫外光非直视传输模型研究 总被引:1,自引:1,他引:0
为了克服紫外光通信中单散射模型在低能见度下的适用局限性,基于一阶多次散射理论,对Luegtten非直视单散射信道模型进行修正。在原模型的建模基础上,修正模型考虑了大气分子的瑞利散射和气溶胶的米氏散射,并且引入了多次散射的影响,运用Matlab对修正模型进行了仿真。结果表明,在低能见度下修正模型比原模型在信道模拟上有较大改进,数据与试验结果吻合得更好;由于一阶多次散射理论适用于多次散射小于单次散射但又不能忽略的情况,修正模型与实际情况存在一定的差距。这对低能见度下的紫外光通信试验提供了参考数据。 相似文献