A variable-geometry combustor used to study primary and secondary zone stoichiometry

A combustion program is underway to evaluate fuel quality effects on gas turbine combustors. A rich-lean variable geometry combustor design was chosen to evaluate fuel quality effects over a wide range of primary and secondary zone equivalence ratios at simulated engine operating conditions. The first task of this effort, was to evaluate the performance of the variable geometry combustor. The combustor incorporates three stations of variable geometry to control primary and secondary zone equivalence ratio and overall pressure loss. Geometry changes could be made while a test was in progress through the use of remote control actuators. The primary zone liner was water cooled to eliminate the concern of liner durability. Emissions and performance data were obtained at simulated engine conditions of 80 percent and full power. Inlet air temperature varied from 611 to 665K, inlet total pressure varied from 1.02 to 1.24 MPa, reference velocity was a constant 1400 K

Evolutionary Algorithms for Reinforcement Learning

There are two distinct approaches to solving reinforcement learning problems, namely, searching in value function space and searching in policy space. Temporal difference methods and evolutionary algorithms are well-known examples of these approaches. Kaelbling, Littman and Moore recently provided an informative survey of temporal difference methods. This article focuses on the application of evolutionary algorithms to the reinforcement learning problem, emphasizing alternative policy representations, credit assignment methods, and problem-specific genetic operators. Strengths and weaknesses of the evolutionary approach to reinforcement learning are presented, along with a survey of representative applications

Stochastic Transition Model for Discrete Agent Movements

We propose a calibrated two-dimensional cellular automaton model to simulate pedestrian motion behavior. It is a v=4 (3) model with exclusion statistics and random shuffled dynamics. The underlying regular grid structure results in a direction-dependent behavior, which has in particular not been considered within previous approaches. We efficiently compensate these grid-caused deficiencies on model level.Comment: 8 pages, 4 figure

The design of linear multivariable control systems using modern control theory /with applications to coupled core reactor control/

Linear multivariable control system design using modern control theory, and application to coupled core reactor contro

Sustainability, stakeholders and business. Editorial

Over the past 20 years, there has been an increasing attention on the drivers of value in organizations. Both the strategic management literature and practice have remarked the importance for managers to be aware of the impact of firm activities, products and services on either the external and internal environment and, more generally, on all firm stakeholders. The emergence of the notions of “sustainable development” and “sustainability” reflects a profound change in global thinking, which forces firms to move beyond trade-offs between business and society

A New Tribe of Saber-toothed Cats (\u3ci\u3eBarbourofelini\u3c/i\u3e) from the Pliocene of North America

A new genus of Pliocene Saber-toothed felid, Barbourofelis, is proposed and two new species B. fricki and B. morrisi are described. These two forms and other described material represent an unusual lineage of felids with long sabers, shortened crania, and massive postorbital bars. The tribal name Barbourofelini is proposed for this lineage which is presently known in North America from deposits ranging in age from Clarendonian through Kimballian. The Barbourofelini apparently migrated from Eurasia to North America in the Late Miocene or Early Pliocene. Sansanosmilus of the French Vindobonian appears to represent the ancestral stock of these cats. The following genera of other saber-toothed felids are discussed: Hoplophoneus, Eusmilus, Dinictis, Nimravus, Ekgmoiteptecela, Ma.chairodus, Ischyrosmilus, Homotherium, H. (Dinobastis), Megantereon, and Smilodon. The two generic names Albanosmilus and Grivasmilus also are considered. The continued usage of the provincial age terms Valentinian and Kimballian is recommended, and a faunal list for these units in Nebraska is provided

Theory of magnetothermomechanics

Journal ArticleWe show that in both ferromagnetic and antiferromagnetic systems with weak magnetostrictive coupling the coefficient of thermal expansion gives a useful measure of the magnetic specific heat. We also analyze the strong coupling situation by means of our simplified, but soluble model, and find it possible to introduce an effective temperature T* and an effective magnetic susceptibility. The exact pressure dependence of the thermodynamic functions can be found, and the pressure dependence of the Curie temperature is given explicitly. In strong coupling, a novel first-order thermodynamic phase transformation can occur which is manifested by a discontinuity in T* as a function of T

Bears (Ursidae) from the Late Cenozoic of Nebraska

A ramus and partial premaxilla establish the presence of a new subspecies of Indarctos in the upper Pliocene (Kimball Formation, Ogallala Group) of Frontier County, Nebraska. An extremely large species of Agriotherium is represented by fragmentary remains from the middle Pliocene (middle part of Ash Hollow Formation, Ogallala Group) of Sherman County, Nebraska. This study is part of a series of papers dealing primarily with the fauna of the Kimball formation in Nebraska (Barbour 1927, 1929; Barbour and Schultz, 1941; Schultz and Stout, 1948, 1961; Kent 1963, 1967; Tanner, 1967; Short, 1969; Martin and Tate, 1970; Schultz, Schultz, and Martin, 1970). The Kimballian fauna from Nebraska differs from the Hemphillian fauna in that most of the known forms are markedly more advanced, but definitely pre-Blancan (Early Pleistocene). A large bear, Indarctos oregonensis keithi, new subspecies, from U.N.S.M. Coli. Loc. Ft-40 is included in the Kimballian fauna from Nebraska. An edentulous ramus and a radius of Agriotherium brought in by Frank Garvel of Ashton, Nebraska, from near U.N.S.M. Coll. Loc. Sm-101 in Sherman County, Nebraska, is also reported. This latter locality is Hemphillian in age (Ash Hollow Formation) and has produced Machairodus as well as some rhinoceros material (personal communication from Lloyd Tanner)