Specimen Orientation for the Calibration of Direct Scanning X-Ray Wood Densitometers

It was found that specimen orientation has considerable effect on the calibration of direct scanning X-ray wood densitometers. A comparison between various orientations was made and verified by a test. Optimum calibration is accomplished when the specimens are made in such a way that the radiation beam is passed through the wood in the tangential direction and scans it in the radial direction

Adaptive multimodal continuous ant colony optimization

Seeking multiple optima simultaneously, which multimodal optimization aims at, has attracted increasing attention but remains challenging. Taking advantage of ant colony optimization algorithms in preserving high diversity, this paper intends to extend ant colony optimization algorithms to deal with multimodal optimization. First, combined with current niching methods, an adaptive multimodal continuous ant colony optimization algorithm is introduced. In this algorithm, an adaptive parameter adjustment is developed, which takes the difference among niches into consideration. Second, to accelerate convergence, a differential evolution mutation operator is alternatively utilized to build base vectors for ants to construct new solutions. Then, to enhance the exploitation, a local search scheme based on Gaussian distribution is self-adaptively performed around the seeds of niches. Together, the proposed algorithm affords a good balance between exploration and exploitation. Extensive experiments on 20 widely used benchmark multimodal functions are conducted to investigate the influence of each algorithmic component and results are compared with several state-of-the-art multimodal algorithms and winners of competitions on multimodal optimization. These comparisons demonstrate the competitive efficiency and effectiveness of the proposed algorithm, especially in dealing with complex problems with high numbers of local optima

N-[2-(2-Hy­droxy­eth­oxy)pheneth­yl]phthalimide

The title compound, C18H17NO4, was obtained accidentally through acid-catalysed aromatization of a phthalimide-substituted 2-(1-hy­droxy­eth­yl)cyclo­hex-2-enone. It exhibits an intra­molecular O—H⋯Oc (c = carbonyl) hydrogen bond and forms a three-dimensional network structure via π–π stacking inter­actions between adjacent benzene rings (phthalimide-to-phenyl­ene and phthalimide-to-phthalimide), with centroid–centroid distances of 3.8262 (6) and 3.6245 (5) Å

A point-in-polygon method based on a quasi-closest point

International audienceThis paper presents a numerically stable solution to a point-in-polygon problem by combining the orientation method and the uniform subdivision technique. We define first a quasi-closest point that can be locally found through the uniform subdivision cells, and then we provide the criteria for determining whether a point lies inside a polygon according to the quasi-closest point. For a large number of points to be tested against the same polygon, the criteria are employed to determine the inclusion property of an empty cell as well as a test point. The experimental tests show that the new method resolves the singularity of a test point on an edge without loss of efficiency. The GIS case study also demonstrates the capability of the method to identify which region contains a test point in a map