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Examining Social Capital and its Role in Special Education Leadership
The purpose of this mixed-methods study was to analyze the relationships that existed between the special education leaders and other members of a district leadership team in order to measure their access to social capital. Quantitative data were collected using surveys of one school districtās leadership team and social network analysis (SNA) was used to visually analyze the connections between members of the team. Qualitative data were subsequently collected via semi-structured interviews of each of the 19 members of the leadership team. What types of ties do the special education administrators have to fellow administrators within district leadership teams? What level of influence do the special education administrators hold as measured by access or position within a district administrative leadership teamās social network? Themes of trust, support/advice, acceptance/reassurance, and collegial relationships emerged as a result of the research. A model conceptualizing the impact and import of social capital in special education leadership within a district leadership team was developed and depicts how themes that emerged in this study can interact with each other to form positive collaborative networks that not only support leaders of special education but all members of the leadership team. Recommendations for future research are included
Transition Delay Using Biomimetic Fish Scale Arrays
Aquatic animals have developed effective strategies to reduce their body drag over a long period of time. In this work, the influence of the scales of fish on the laminar-to-turbulent transition in the boundary layer is investigated. Arrays of biomimetic fish scales in typical overlapping arrangements are placed on a flat plate in a low-turbulence laminar water channel. Transition to turbulence is triggered by controlled excitation of a Tollmien-Schlichting (TS) wave. It was found that the TS wave can be attenuated with scales on the plate which generate streamwise streaks. As a consequence, the transition location was substantially delayed in the downstream direction by 55% with respect to the uncontrolled reference case. This corresponds to a theoretical drag reduction of about 27%. We thus hypothesize that fish scales can stabilize the laminar boundary layer and prevent it from early transition, reducing friction drag. This technique can possibly be used for bio-inspired surfaces as a laminar flow control means
Satellite geological and geophysical remote sensing of Iceland: Preliminary results of geologic, hydrologic, oceanographic, and agricultural studies with ERTS-1 imagery
The author has identified the following significant results. The wide variety of geological and geophysical phenomena which can be observed in Iceland, and particularly their very direct relation to the management of the country's natural resources, has provided great impetus to the use of ERTS-1 imagery to measure and map the dynamic natural phenomena in Iceland. MSS imagery is being used to study a large variety of geological and geophysical eruptive products, geologic structure, volcanic geomorphology, hydrologic, oceanographic, and agricultural phenomena of Iceland. Some of the preliminary results from this research projects are: (1) a large number of geological and volcanic features can be studied from ERTS-1 imagery, particularly imagery acquired at low sun angle, which had not previously been recognized; (2) under optimum conditions the ERTS-1 satellite can discern geothermal areas by their snow melt pattern or warm spring discharge into frozen lakes; (3) various maps at scales of 1:1 million and 1:500,000 can be updated and made more accurate with ERTS-1 imagery; (4) the correlation of water reserves with snowcover can improve the basis for planning electrical production in the management of water resources; (5) false-color composites (MSS) permitted the mapping of four types of vegetation: forested; grasslands, reclaimed, and cultivated areas, and the seasonal change of the vegetation, all of high value to rangeland management
Ultrafast preparation and strong-field ionization of an atomic Bell-like state
Molecules are many body systems with a substantial amount of entanglement
between their electrons. Is there a way to break the molecular bond of a
diatomic molecule and obtain two atoms in their ground state which are still
entangled and form a Bell-like state? We present a scheme that allows for the
preparation of such entangled atomic states from single oxygen molecules on
femtosecond time scales. The two neutral oxygen atoms are entangled in the
magnetic quantum number of their valence electrons. In a time-delayed probe
step, we employ non-adiabatic tunnel ionization, which is a magnetic quantum
number-sensitive mechanism. We then investigate correlations by comparing
single and double ionization probabilities of the Bell-like state. The
experimental results agree with the predictions for an entangled state.Comment: 20 pages, 7 figures, 1 tabl
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