4,182 research outputs found
On small homotopies of loops
Two natural questions are answered in the negative:
(1) If a space has the property that small nulhomotopic loops bound small
nulhomotopies, then are loops which are limits of nulhomotopic loops themselves
nulhomotopic?
(2) Can adding arcs to a space cause an essential curve to become
nulhomotopic?
The answer to the first question clarifies the relationship between the
notions of a space being homotopically Hausdorff and -shape injective.Comment: 12 pages, 5 figure
Active controls for ride smoothing
Active controls technology offers great promise for significantly smoothing the ride, and thus improving public and air carrier acceptance, of certain types of transport aircraft. Recent findings which support this promise are presented in the following three pertinent areas: (1) Ride quality versus degree of traveler satisfaction; (2) significant findings from a feasibility study of a ride smoothing system; and (3) potential ride problems identified for several advanced transport concepts
Sandstones of the Lance and Fort Union Formations
The Fort Union and Lance formations are widespread terrestrial sediments exposed in Montana, North Dakota, South Dakota, Wyoming, and Canada. Their stratigraphic position, especially that of the Lance, has long been in doubt, and has provoked much controversy among geologists
Student Interactions, Connectedness, and Retention in an Online MBA Program: An Exploratory Study
The market for online education is competitive, especially for graduate programs such as the Master of Business Administration (MBA). Attrition rates vary widely, and educators must understand the needs of online students and create engaging quality programs to be competitive. Social interaction and student connectedness are particularly important in online MBA programs where one of the expected benefits is the opportunity for students to build strong professional networks. This mixed methods study explores the student interactions, connectedness, and retention in the Online MBA Program at William & Mary. While previous research has explored building community in an online educational environment, a gap remains in the literature regarding the quality and type of student connections in a part-time online graduate program tailored to working professionals. In addition to surveying faculty who taught in the program, I attempted to survey all students of the program and used the results of the Online Student Connectedness Survey (Bolliger & Inan, 2012) to inform the student participant selection process for the qualitative case study. Rooted in the social constructivist paradigm, I created the Online Student Connectedness conceptual framework and sought to determine the extent to which students and alumni of the program felt connected. I also wanted to determine what the students’ experiences of connectedness were and the quality of those connections. The results of the quantitative survey revealed a moderately high perception of connectedness among students in the program. The results of the qualitative data indicated that several factors influenced the students’ experiences of connectedness. In addition to carefully planned collaborative and group work, a feeling of comfort and perception of community were key factors. Managing students’ expectations, support from others, and connection to the institution contributed positively to the high retention rate enjoyed by the program. The results of the study offer a number of implications for practice that may be beneficial to program administrators, professors, course developers, instructional designers, and to students. Through appropriate application of social constructivist theory and adult learning theory, educators can create learning activities that promote student connectedness and thereby, increase student satisfaction and retention rates
Design and development of a water vapor electrolysis unit
Design and development of water vapor electrolysis unit for oxygen productio
IUSThrust Vector Control (TVC) servo system
The IUS TVC SERVO SYSTEM which consists of four electrically redundant electromechanical actuators, four potentiometer assemblies, and two controllers to provide movable nozzle control on both IUS solid rocket motors is developed. An overview of the more severe IUS TVC servo system design requirements, the system and component designs, and test data acquired on a preliminary development unit is presented. Attention is focused on the unique methods of sensing movable nozzle position and providing for redundant position locks
Titanium alloy stress corrosion cracking in presence of dinitrogen tetroxide
Study resulting in a satisfactory stress corrosion cracking test with extremely consistent results produced six new analytical methods. Methods detect and determine differences in the minor constituent composition of different types of dinitrogen tetroxide
On the relation of Voevodsky's algebraic cobordism to Quillen's K-theory
Quillen's algebraic K-theory is reconstructed via Voevodsky's algebraic
cobordism. More precisely, for a ground field k the algebraic cobordism
P^1-spectrum MGL of Voevodsky is considered as a commutative P^1-ring spectrum.
There is a unique ring morphism MGL^{2*,*}(k)--> Z which sends the class
[X]_{MGL} of a smooth projective k-variety X to the Euler characteristic of the
structure sheaf of X. Our main result states that there is a canonical grade
preserving isomorphism of ring cohomology theories MGL^{*,*}(X,U)
\tensor_{MGL^{2*,*}(k)} Z --> K^{TT}_{- *}(X,U) = K'_{- *}(X-U)} on the
category of smooth k-varieties, where K^{TT}_* is Thomason-Trobaugh K-theory
and K'_* is Quillen's K'-theory. In particular, the left hand side is a ring
cohomology theory. Moreover both theories are oriented and the isomorphism
above respects the orientations. The result is an algebraic version of a
theorem due to Conner and Floyd. That theorem reconstructs complex K-theory via
complex cobordism.Comment: LaTeX, 18 pages, uses XY-pi
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