2,484 research outputs found
Generalizations of Ripley's K-function with Application to Space Curves
The intensity function and Ripley's K-function have been used extensively in
the literature to describe the first and second moment structure of spatial
point sets. This has many applications including describing the statistical
structure of synaptic vesicles. Some attempts have been made to extend Ripley's
K-function to curve pieces. Such an extension can be used to describe the
statistical structure of muscle fibers and brain fiber tracks. In this paper,
we take a computational perspective and construct new and very general variants
of Ripley's K-function for curves pieces, surface patches etc. We discuss the
method from [Chiu, Stoyan, Kendall, & Mecke 2013] and compare it with our
generalizations theoretically, and we give examples demonstrating the
difference in their ability to separate sets of curve pieces.Comment: 9 pages & 8 figure
Three birds from the mountains of Muscat
Dr. W. Wells Thorns, a resident of Muttrah in Muscat, has been kind enough to send me several specimens of the flora and fauna from the Jebel Akhdar Mountains which lie within the territory of the Sultanate of Muscat and Oman in southeastern Arabia. Three bird specimens taken among the fruit trees near the village of Seik at 6300 feet above sea level are most interesting as affording the first recorded specimens from this mountain range
New birds from the western Papuan islands
As a preliminary to further publications on the work of the 1954 Yale Peabody Museum Expedition to the Moluccas, I should like to describe the following new forms of birds collected on the trip undertaken by myself and my wife…
Notes on Indian birds. VII.
In my forthcoming hand-list of Indian birds, I have treated the White-cheeked Bulbuls as belonging to a single species…
Comments on birds from the western Papuan islands
Opportunities for visiting Kofiau Island (often called Koffiao, Kavijave, Kavijaaw, or Poppa in the literature) are few and far between…
Notes on Indian birds. VI. Additional comments on the Wren-babbler, Spelaeornis
At the suggestion of Dr. Walter Koelz, I have assembled a number of specimens of Spelaeornis, the small Wren-babbler whose status I reviewed in 1950 (Auk, 67:390-391), and again in 1952..
A note on the Firethroat and the Blackthroated Robin
While on a visit to the U.S.S.R. recently, I had the opportunity of examining two specimens of the small chat, the Black-throated Robin
Two new birds from Angola
During the course of his first collecting trip for the Peabody Museum in Angola, Mr. Gerd Heinrich secured two interesting new birds in Malange District in the northeast of that fascinating Country. The Museum is most grateful to the Department of Overseas of the Government of Portugal, the Government officials in Luanda and the officials of the Diamond Company who aided Mr. and Mrs. Heinrich unstintingly during their expedition
Birds from Djailolo, Halmahera
My wife and I had the opportunity of spending a week in the vicinity of Djailolo on the island of Halmahera from September 2 through 8, 1954, during a trip in the Moluccas sponsored partly by the Guggenheim and National Science Foundations as well as Yale University...
A new race of black-throated babbler from Assam
The Mishmi Hills in northeastern Assam, India, were so violently devastated by the great earthquake of August 1950 that whole hillsides for miles along the narrow steep valleys have been denuded of soil and vegetation…
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