22,988 research outputs found
New State Records For Some Predatory And Parasitic True Bugs (Heteroptera: Cimicomorpha) of the United States
Forty new state records, distributed among Anthocoridae, Cimicidae, Lasiochilidae, Lyctocoridae, Nabidae, and Reduviidae, are reported for 25 species of Cimicomorpha found in the United States
New State Records and Distributional Notes for Some Assassin Bugs of the Continental United States (Heteroptera: Reduviidae)
One hundred sixty-eight new state records are presented for 51 species of assassin bugs found in the United States; distributional and taxonomic notes supplement the records. The current known distribution north of Mexico is provided for each species
Confirmed Presence of the Ambush Bug \u3ci\u3ePhymata vicina vicina\u3c/i\u3e (Heteroptera: Reduviidae: Phymatinae) in Michigan
The ambush bug Phymata vicina vicina Handlirsch, 1897 (Reduviidae: Phymatinae) is reported from Michigan for the first time, corroborating prior predictions. An additional couplet is provided to amend the previous key to the phymatine species of Michigan
New State Records For Some Pentatomomorpha (Heteroptera) of the United States
Forty-two new state records, distributed among the Alydidae, Coreidae, Largidae, Pyrrhocoridae, and Rhopalidae, are reported for 25 species of Pentatomomorpha found in the United States
A Synopsis of the Coreoidea (Heteroptera) of Michigan
An overview of the species of Coreoidea (Alydidae, Coreidae, and Rhopalidae) found in Michigan is presented, along with identification keys, distribution maps, and relevant literature. New state records for Alydus pilosulus Herrich-Schaeffer (Alydidae: Alydinae), Merocoris distinctus Dallas (Coreidae: Meropachyinae), Leptoglossus corculus (Say) (Coreidae: Coreinae), Leptoglossus oppositus (Say) (Coreidae: Coreinae), and Liorhyssus hyalinus (Fabricius) (Rhopalidae: Rhopalinae) are included
An Out of Sample Test for Granger Causality
Granger (1980) summarizes his personal viewpoint on testing for causality, and outlines what he considers to be a useful operational version of his original definition of causality (Granger (1969)), which he notes was partially alluded to in Wiener (1958). This operational version is based on a comparison of the 1-step ahead predictive ability of competing models. However, Granger concludes his discussion by noting that it is common practice to test for Granger causality using in-sample F-tests. The practice of using in-sample type Granger causality tests continues to be prevalent. In this paper we develop simple (nonlinear) out-of-sample predictive ability tests of the Granger non-causality null hypothesis. In addition, Monte Carlo experiments are used to investigate the finite sample properites of the test. An empirical illustration shows that the choice of in-sample versus out-of-sample Granger causality tests can crucially affect the conclusions about the predictive content of money for output.
Tether crawler system
A crawler system is designed to move a low-g/variable-g laboratory module along a tether between the Space Station and an attached space platform. An analysis is made of the effects of control law parameter change on the displacement, velocity, and acceleration of the crawler system. The control law is then modified by the addition of a constant-velocity section and the values of distance traveled, velocity, and acceleration are analyzed as a function of time. The power and torque equations are derived for a crawler system moving along a tether in orbit and numerical values of power and torque required for each prescribed movement are calculated versus time for four different cases using the control laws. A two-step control sequence is selected to permit initial location along the tether by distance traveled, followed by a vernier movement to reach the final desired constant net acceleration level. The components for the control system are identified and arranged in a block disgram configuration. The support subsystems are also identified. The sections were integrated to develop a procedure for the determination of crawler system performance requirements and the initial design of tether crawler systems
Measurement of minority carrier transport parameters in heavily doped n-type silicon
Measurement of minority transport parameters in heavily doped silicon is covered. The basic transport equations were used to define two independent parameters. Use of special vertical and lateral transistor test devices permitted the measurement of both parameters. Prior studies were normalized to show excellent agreement over the heavy doping region
Combinatorial Solutions Providing Improved Security for the Generalized Russian Cards Problem
We present the first formal mathematical presentation of the generalized
Russian cards problem, and provide rigorous security definitions that capture
both basic and extended versions of weak and perfect security notions. In the
generalized Russian cards problem, three players, Alice, Bob, and Cathy, are
dealt a deck of cards, each given , , and cards, respectively.
The goal is for Alice and Bob to learn each other's hands via public
communication, without Cathy learning the fate of any particular card. The
basic idea is that Alice announces a set of possible hands she might hold, and
Bob, using knowledge of his own hand, should be able to learn Alice's cards
from this announcement, but Cathy should not. Using a combinatorial approach,
we are able to give a nice characterization of informative strategies (i.e.,
strategies allowing Bob to learn Alice's hand), having optimal communication
complexity, namely the set of possible hands Alice announces must be equivalent
to a large set of -designs, where . We also provide some
interesting necessary conditions for certain types of deals to be
simultaneously informative and secure. That is, for deals satisfying
for some , where and the strategy is assumed to satisfy
a strong version of security (namely perfect -security), we show that and hence . We also give a precise characterization of informative
and perfectly -secure deals of the form satisfying involving -designs
Flat conductor cable survey
Design handbook contains data and illustrations concerned with commercial and Government flat-conductor-cable connecting and terminating hardware. Material was obtained from a NASA-sponsored industry-wide survey of approximately 150 companies and Government agencies
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