23,812 research outputs found
Revision of the weevil genus Epimechus Dietz (Coleoptera: Curculionidae: Anthonomini)
Epimechus curvipes Dietz is designated as type species of the genus Epimechus Dietz. Ten additional species from western North America, including four new species, are assigned to the genus: E. aemulus Fall; E. flavirostris Fall; E. mimicus Dietz; E. adspersus Dietz; E. mobilis Fall; E. nevadicus Dietz; E. molina, new species (Arizona, Baja California Norte); E. combustus, new species (Arizona, New Mexico, Utah); E. signum, new species (Arizona, Coahuila, Colorado, New Mexico, Saskatchewan, Texas, Utah) and E. hesperius, new species (Arizona, California, Colorado, Guanajuato, Idaho, Nevada, New Mexico, Nuevo Leon, South Dakota, Texas, Utah, Wyoming). These are distinguished from other Anthonomini by the short, simple tarsal claws. The names Epimeclws modicus Fall, E. soriculus Dietz, and E. nanulus Fall are placed in new synonymy under E. curvipes. Lectotypes are designated for E. adspersus and E. nevadicus. Two species formerly in Epimechus are transferred the subgenus Cnemocyllus Dietz in Anthonomus Germar: E. arenicolor Fall as Anthonomus arenicolor (Fall), new combination, and E. canoides Fall as Anthonomus canoides (Fall), new combination. Adults of species of Epimechus have been collected on plants in the genera Baccharis, Chrysothamnus, Ericameria, Gutierrezia, Haplopappus, Senecio and Tetradymia (all Asteraceae)
The Anthonomus juniperinus group, with descriptions of two new species (Coleoptera: Curculionidae)
The Anthonomus juniperinus (Sanborn) species group is defined and two new species, Anthonomus sanborni, new species, and A. rileyi new species, from the United States are described, keyed and illustrated. The three species of the group are associated with the plant genus Juniperus and the larvae of A. juniperinus are known to develop in fungal galls of Gymnosporangium spp. as well as fruits of the Eastern redcedar, Juniperus virginiana L. The biology of the group and its taxonomic relationships to other species of Anthonomus Germar are also discussed
Revision of the subgenus Cnemocyllus Dietz of the weevil genus Anthonomus Germar (Coleoptera: Curculionidae, Anthonomini)
Anthonomus (Cnemocyllus) decipiens Dietz is designated as type species of Cnemocyllus Dietz. The twenty-three North American species assigned to the Anthonomus subgenus Cnemocyllus include ten previously placed in the subgenus: A. albus Hatch, A. decipiens LeConte, A. dorothyae Hatch, A. elongatus LeConte, A. jacobinus Dietz, A. juncturus Fall, A. ligatus Dietz, A. pictus Blatchley, A. quesnelensis Sleeper, and A. tenuis Fall; three species formerly in Anthonomus but not in Cnemocyllus: A. stolatus Fall, A. inermis Boheman, and A. ornatulus Dietz; two species once in Epimechus Dietz but subsequently transferred to Anthonomus: A. arenicolor (Fall) and A. canoides (Fall); and eight new species: A. californiensis, new species (California and Baja California); A. bajaensis, new species (Baja California); A. intermedius, new species (Utah); A. extensus, new species (British Columbia, California, Idaho, Oregon, and Washington); A. deserticolus, new species (Arizona, Baja California, California, Guerrero, New Mexico, Sonora, and Texas); A. schuhi, new species (California and Oregon); A. latus, new species (California); and A. squamoerectus, new species (California and Oregon). The species of Anthonomus in the subgenus Cnemocyllus are distinguished from other Anthonomini by the combination of having vestiture of more-or-less broad, dense scales, 6 or 7 antennal funicular articles, a slender endophallic transfer apparatus and, in most, the slightly to strongly curved metatibia of the male. The tarsal claws are variable, toothed or untoothed. The names Anthonomus cycliferus (Fall), A. malkini Hatch and A. summeri Hatch are placed in new synonymy under A. jacobinus Dietz; A. cretaceus (Champion) is placed in new synonymy under A. decipiens LeConte; A. imbricus Hatch is placed in new synonymy under A. quesnelensis Sleeper; A. mannerheimi Dieckmann (A. brunnipennis Mannerheim, not Curtis) and A. subvittatus LeConte are placed in new synonymy under A. inermis (Boheman); A. minutus Hatch is placed in new synonymy under A. dorothyae Hatch. Adults of many of the species of the subgenus Cnemocyllus have been collected on plants in the family Asteraceae. The larvae of several of the species are known to develop on these plants
Results of literature search on dielectric properties and electron interaction phenomena related to spacecraft charging
The objective of the literature search was to determine the required material properties and electron interaction parameters needed for modeling charge buildup and breakdown in insulators. A brief overview of the results of the literature search is given. A partial list of the references covered is included in a bibliography. Although inorganic insulators were also considered in the search, coverage is limited to the organics, primarily Kapton and Teflon
First and second simulator evaluations of advanced integrated display and control systems
Advanced integrated visual and control systems simulator evaluations for post-Apollo manned spacecraf
A Component Based Heuristic Search Method with Evolutionary Eliminations
Nurse rostering is a complex scheduling problem that affects hospital
personnel on a daily basis all over the world. This paper presents a new
component-based approach with evolutionary eliminations, for a nurse scheduling
problem arising at a major UK hospital. The main idea behind this technique is
to decompose a schedule into its components (i.e. the allocated shift pattern
of each nurse), and then to implement two evolutionary elimination strategies
mimicking natural selection and natural mutation process on these components
respectively to iteratively deliver better schedules. The worthiness of all
components in the schedule has to be continuously demonstrated in order for
them to remain there. This demonstration employs an evaluation function which
evaluates how well each component contributes towards the final objective. Two
elimination steps are then applied: the first elimination eliminates a number
of components that are deemed not worthy to stay in the current schedule; the
second elimination may also throw out, with a low level of probability, some
worthy components. The eliminated components are replenished with new ones
using a set of constructive heuristics using local optimality criteria.
Computational results using 52 data instances demonstrate the applicability of
the proposed approach in solving real-world problems.Comment: 27 pages, 4 figure
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