Glass transition studies in free standing polymer films have revealed values of the transition temperature, T(g), which were substantially reduced below the bulk for sufficiently thin films. Here we report on the preparation of two stacks of free standing polystyrene films: 70 films with a thickness of h approximately 107 nm and 140 films with h approximately 55 nm with equivalent total sample ...

The geometry of feather barbs (barb length and barb angle) determines feather vane asymmetry and vane rigidity, which are both critical to a feather's aerodynamic performance. Here, we describe the relationship between barb geometry and aerodynamic function across the evolutionary history of asymmetrical flight feathers, from Mesozoic taxa outside of modern avian diversity (Microraptor, Archaeo...

Wing-assisted incline running (WAIR) in birds combines the use of the wings and hindlimbs to ascend otherwise insurmountable obstacles. It is a means of escape in precocial birds before they are able to fly, and it is used by a variety of juvenile and adult birds as an alternative to flight for exploiting complex three-dimensional environments at the interface of the ground and air. WAIR and co...

Micro-X is an X-ray sounding rocket payload that had its first flight on July 22, 2018. The goals of the were to operate a transition edge sensor (TES) microcalorimeter array in space and take high-resolution spectrum Cassiopeia A supernova remnant. was considered partial success. time-division multiplexing readout system successfully operated space, but due failure attitude control system, no ...

Title of thesis: EXPERIMENTAL INVESTIGATION OF A QUAD-ROTOR BIPLANE MICRO AIR VEHICLE Christopher Michael Bogdanowicz Master of Science, 2015 Thesis directed by: Dr. Inderjit Chopra Department of Aerospace Engineering Micro air vehicles are expected to perform demanding missions requiring efficient operation in both hover and forward flight. This thesis discusses the development of a hybrid air...

Gibbons are able to brachiate effectively through the forest canopy with a suspended swinging motion via contact with handholds. The swing phase is unlikely to be a cause of significant energy loss as pendulums are able to oscillate with only gradual mechanical energy dissipation. We consider the energetics associated with the transition of either a swing (during continuous-contact brachiation)...

Improvement of the launch phase of a jet powered Unmanned Aerial Vehicle (UAV) with Jet Assisted Take Off (JATO), has been the subject of attention in the UAV industry. Use of flight simulation tools reduces the risk and required some amount of flight testing for complex aerospace systems. Full nonlinear equations of motion are used to study and simulate this maneuver and three case studies of ...

Nowadays, in-flight comfort has become an essential characteristic to survive in domestic airline businesses. Air hostesses’ quality of service and response time to customer demand plays a vital role in enhancing quality of the flight experience and passenger satisfaction. However, additional requirements on air hostess expose them to fatigue which could eventually result in job dissatisfac...

T he business environment is characterized by environmental and exogenous factors that affect company performance to the extent that it prevents managers from interacting effectively with a company. This study built on the literature on the ease of doing business and capital flight by empirically demonstrating the importance of business environments across different countries. To thi...

the cuckoo search algorithm is a recently developedmeta-heuristic optimization algorithm, which is suitable forsolving optimization problems. to enhance the accuracy andconvergence rate of this algorithm, an improved cuckoo searchalgorithm is proposed in this paper. normally, the parametersof the cuckoo search are kept constant. this may lead todecreasing the efficiency of the algorithm. to cop...